2001 or thereabouts brought us the 7mm Whizzum, aka 7mm Winchester Short Magnum(WSM)....a sorta stout,vertically challenged affair and really a copy of a design that originated back in the 50's in the Gradle Express line
But also back around the 1950's a guy from Oklahoma named Art Mashburn(actually known by OU76 who posts on here)gave us,after much experimenting,the cartridge known as the 7mm Mashburn Super Magnum,aka 7mm MSM.The Gradle Express series went nowhere at the time, but the Mashburn was popularized by such notables as Bob Hagel and Warren Page back in the 50's and 60's;and by our own Mark Dobrenski today.
(Worth noting here the 7mm Weatherby was around in proprietary form, but Roy gave his barrels a 12 twist which did not stabilize the 160 gr bullets that LR elk hunters wanted to use.)
Unlike the WSM, the MSM is a long, leggy affair that can fit handily into a 30/06 length action,but adapts nicely to a H&H-length action as well, which means any run of the mill Remington 700 or Winchester M70 can be adapted to it.
After fully half a lifetime (30 years) of using the 7RM, I wanted something a little different in the way of a portable,relatively lightweight all-round BG rifle,with the ability to "easily"(a key component)push a 175 gr 7mm bullet in excess of 3000 fps,a 160 gr from 3150-3200 fps, from a 24" barrel,with moderate powder charges,and would not kick me into next week.Something "optimum" but not too much,as with the 7STW and the Ultra Mag,both of which seem more at home with thick, heavy 26" tubes and/or gobs of powder.The 7 RM with various throatings came close in a 24" barrel but I sometimes thought I was pushing the envelope;I always thought the 7RM could use more capacity and a longer neck.
After watching Dober's results on here with the Mashburn,and talking to him a good bit,I sent a #2 9 twist Krieger to Gene Simillion,along with a M70 Classic action from a 270.A friend from back here did the same thing.Dober was kind enough to lend us his reamer and I am still using Dobers dies until mine show up from RCBS(we had an ordering snafu with another die maker which delayed having dies delivered on time)....
I told Gene I wanted a 375H&H-length box,and he got me an Echols box which easily swallows cartridges loaded to about 3.575 OAL,with room to spare;throating was set up for a 160 Partition with base of bullet even with base of neck;the 175 seats a bit deeper into the case.
The stock is an Echols Legend Edge;very nice!
So what did I end up with here? Well, as Gene said the cartridge is not about ultimate speed;it's about building a portable package for mountain and open country hunting with an optimum velocity level, with long 7mm heavyweights, reasonable powder consumption,and flat trajectory,and without the weight and recoil of a 300 magnum.Near as I can tell, he described it spot-on....
Load development is still in progress but what I am seeing so far is:
Dobers fireform load of 65 IMR 4350 139 Hornady at 3160 to 3190,(which to me is a 280AI in a similarly configured rifle. The Mashburn will of course push a 139-140 gr bullet much faster with full loads).
After fireforming, you have the blown out Mashburn.And 72.5-73 gr H1000 gives the 175 Nosler Partition 3040 to 3075.This bullet has an SD of .310 and a BC of .519.According to the Nosler tables, when started at these velocities,it has about the same trajectory as a 180 gr 30 caliber Partition started at 3200 fps...(the 30 caliber taking a bunch more powder and recoil to get there). My shooting so far is showing this to be true.
Or if you like plastic tips, this cartridge easily starts a 160 AB at 3150-3175 with about 75 gr H1000.I see no logical reason to go with any bullet weighing less from this case,although you can certainly do it.
As to recoil? I have sat behind a bunch of blown out 300's over the years.In comparison, with its' heaviest loads, this rifle is a cakewalk.
Pretty hard to justify the wildcat in light of all the other 7mm's that provide similar performance;but this one "gets there" in an efficient fashion,being just enough without being too much, yet not lacking the capacity, so that one does not have to stand on it to get the desired velocities,as with smaller 7 mags.And the MSM does this in a 24" barrel to boot.
I have had a 7mm Dakota, which is similar,but did not like being tied to one source of brass, and a case not easily formed from anything else.The MSM can be easily formed from 300 Win Mag cases,available anywhere.And if I get tired of the wildcat,a 7 RM is only a rebarrel job away.
Looks to me like Mashburn,Page,Hagel,and Dober knew (know)what they were talking about,even back 60 years ago!A very cool cartridge!
always thought the Mashburn would be the best 7 mag in creation , but it seems to me that if pushing 175s over 3000 and 160s to 3200 . then recoil has to be alot like a 300Winny ?
SD: It really isn't...it is just "lighter" somehow..hard for me to explain,and don't get me wrong, it recoils.... but I notice a level of muscle tension needed with the big 30's,and a level of fatigue that sets in with the 300's, not present with this and the 7RM.
Might be nitpicking I know(much of this project is ,
....but even Gene said it was a pleasure to shoot compared to the 300's.So at least I know it ain't just me
At 60, I am a lOT more recoil sensitive than I used to be
Bob, do you see any advantage over the weatherby chambering? (one I've thought about) I always "felt" the remington mag was "not quite there", but close!
Good luck with the rifle. Sounds very well thought out and just what you are looking for. I understand the recoil issue but at those velocities, there must be some kick, how is it in comparison to the 7 STW's you have shot?
Don't feel bad, at 41 my recoil tolerences are not what they used to be
pat I have never worked with a 7 Weatherby,and know the manuals show it similar to the Mashburn;but i also know it has about the same capcity as the Remington case,so I really can't explain how the weatherby gets where it does,except due to the freebore,a 26" tube,and Weatherby-type pressures.
I have had a few "long throat" 7 RM's and they nudge right into 7 Weatherby load data territory.But again, I always felt I was leaning a bit hard.The thing that struck me about the Mashburn was how "easily" it reached these velocities.And velocitiy variations are very low,maybe 10 fps in a 5 shot string,at least with H1000.I think Art Mashburn did his homework.
Chip; Thanks!The STW's I have fired were the M70 Classics,longer, heavier rifles,so it is hard to compare;this stock design of D'Arcy's is very good at mitigating rcoil in a magnum chambering.i fired the rifle off hand yesterday and it is very pleasant,not inclined to jump back hard or climb during recoil.It is more manageable than the 300's, to me anyway.
BTW I gotta give credit where it's due....my buddy Matt took the other Krieger #2 and built the same rifle,metal by Gene,and stock work by Charlie;veddy nice also and Charlie did a great job on the stock.
Yesterday at the range Matt said...."I'm gonna shoot the "Mizzum"........I said "The what?"...he said. "You know,the Mashburn Super Magnum, the MSM!" I laughed!
Britt; It is a necked down 300 WM case;first pass with the form die forms the new shoulder and longer neck;second pass with the trim die brings the neck down to 7mm(no trimming required,then through the FL die to tighten up the neck.(Dober had to walk me through all this).
FFing the case blows it out to a straighter contour;the 300 Win Mag has more taper and a shorter neck.
The longer neck is part of the beauty of the Mashburn design, plus the straighter case,which gives a skosh more capacity. The longer neck helps if you build with a longer throat,as I did, because I can seat even 140 gr bullets close to the lands.No bullet I have used is seated into the case,except the 175, and that very little.
The 160 AB is seated to about 3.575 OAL;and the 175 Partition to about 3.515,due to the ogive mostly.
At the end of the day, I doubt there would be much practical difference between the Mashburn and the 300 WM necked down.
Britt; It is a necked down 300 WM case;first pass with the form die forms the new shoulder and longer neck;second pass with the trim die brings the neck down to 7mm(no trimming required,then through the FL die to tighten up the neck.(Dober had to walk me through all this).
FFing the case blows it out to a straighter contour;the 300 Win Mag has more taper and a shorter neck.
The longer neck is part of the beauty of the Mashburn design, plus the straighter case,which gives a skosh more capacity. The longer neck helps if you build with a longer throat,as I did, because I can seat even 140 gr bullets close to the lands.No bullet I have used is seated into the case,except the 175, and that very little.
The 160 AB is seated to about 3.575 OAL;and the 175 Partition to about 3.515,due to the ogive mostly.
At the end of the day, I doubt there would be much practical difference between the Mashburn and the 300 WM necked down.
Sounds suspiciously like a .284 Jarret designed by the greatest gunmaker in the whole wide world
MtnHntr:There is no doubt Dober knows the Mashburn....he helped make this a pretty easy deal,and was spot on in loads vels, etc.he and Gene got me started really well...been an easy wildcat to deal with.
Hillbilly; Thanks I think it turned out pretty good....easy cartridge to work with....no BS...just gives the promised velocities easily.
Randy, yes I will take it to Wyoming Zeroed for the 175 to hit POA at 300 yards, it prints the FF load to the same elevation at 300 yards;but slightly left.
The 160 AB and Partition go to the same POI at 300 yards but about 2" higher than the 175. I would have to rezero for that load....no biggie....
SU: Thanks! Hell all I did was pay for it ....this was a collaborative effort with Dober and Gene providing all the guidance and building.I told Gene what I wanted, specified throat,mag box, etc.He is a dream to work with;a real rifle guy who "gets it" when you mention something....immediately.
Dober was a huge help,advising on the cartridge loads, providing reamer to Gene and dies to me to get mestarted ay great inconvenience. he knows his way around the cartridge and between he and Gene, load work was easy.
Also JWP gave me some good advise on powders as well....I had a LOT of help.
Tell ya what....now I understand what Page was saying about that 175; and he had the old semi-spitzer, not the newer one with that 519 BC,which is pretty darn high for a soft-point Partition.....you could very easily use just that bullet for everything.I have no prior experience with it but Dober gives great reports on it;it shoots flat at 3050,and groups at 100 yards have gone 1/2", if I am on my game.
It do shoot pretty flat -27 at 500 for the 175 started at 3050 and -25 for the 160 Partition started at 3150. Plus calculated recoil of ~ 30-32 ft/lbs for an 8.25 lb gun.
Bob, Great looking rifle and a cool cartridge. Can you give more specifics on the metal work that Gene did (have any pics of that?). What contour barrel..is that an Echol's contour? Also how was rifle bedded..are you using a pressure point on the forend or free float. Terry
Bob, Great looking rifle and a cool cartridge. Can you give more specifics on the metal work that Gene did (have any pics of that?). What contour barrel..is that an Echol's contour? Also how was rifle bedded..are you using a pressure point on the forend or free float. Terry
Terry:I'll try to cover that stuff, best I can.It's written down somewhere
The barrel is a #2 krieger CM that I had here.I can tell it has been machined to sharpen the transition from the chamber area into the barrel shank,just enough to give a definitve edge.He cut and crowned to finish up at 24".The barrel has also been "drawn" (and polished?)before it was blued;you can tell holding it to the light because there is not a wave, or ripple in the blue job anywhere...just straight lines;ditto the action.
He blueprinted the action,squared up the lugs, etc,all the good stuff done when barreling up these days.
He installed an Echols H&H-length box magazine,and a Dakota-type follower.My first round down sits on the left rail.Extractor is a Williams and you can put a cartridge on the bolt face and swing it around;it won't drop a cartridge..... and who knows what he did to the extractor/ejection system but it feeds, extracts, ejects reliably everytime...I have rapid fired it and it gooses empties a long way.I am certain he modified the ejector/bolt stop to handle the H&H length cartridges.
Dunno what he did,but the action doesn't "feel" anything like it did when I sent it to him.It feels somehow "tighter",less play and slop,smoother overall.
Bottom metal is Williams and has been recontoured so that the trigger guard tapers to the rear toward the back screw;nice touch...it's also nicely blued and polished.
Mounts are leupold DD's which I requested;they are ground to the receiver.He changed screw spacing on the bridge;I think this was done because he machined the bridge to allow use of a H&H-length round(This is what I like about Gene;this is a small item that you don't have to mention to him;when you say set it up for H&H length, he knows EXACTLY what is required;does the whole thing "right").
The bolt handle is the original M70 Classic, recontoured.He notched the cocking piece shroud so that in the fire position the arm of the safety makes no contact.Nice little touch.
I am sure he machined/polished the bolt body as there is no visible seam where the bolt handle is fixed to the bolt body. The bolt body is jeweled,which I like.Bolt release is built up and checkered.The trigger is the original,but he contoured it to a slender profile.It really feels great and breaks like glass.I asked for 3.5 pounds but whatever....from off hand it broke nicely when I said "go".
The sling swivel studs are a nice two screw design,perfectly inletted.There are a lot of subtle touches in the rifle that make it a nice package.
Overall everything is just tighter,slicker,nicer feeling than when I sent it to him.It's apparent that he paid a lot of attention to small details here as there are lots of little touches making a nice package.
I knew going in that a #2 chambered for a cartridge of this power was on the light side for a powerful high velocity cartrdige;and the Edge stock is light as well.I had heard that D'Arcy does not like to use an Edge on anything bigger than 300 Win Mag.I suspect Gene felt the same way.I could have gone heavier in both the barrel and stock but figured it would shoot regardless because it was put together well...but I wanted a portable rifle that while not being too heavy,was not too light either.That said, I knew I was on the ragged edge with this chambering.that said, this ain't a BR rifle....it's meant for hunting.
It shoots very well,not to BR standards,but groups with the form load and the 160's are sub MOA and enough 1/2" 3 shot groups show up to know I am likely the limiting factor.
When I got to the 175's though, at full velocity, the wheels fell off...groups were in the 2" range.Also, shot from my hands ,field prone at 300 yards,it showed a tenedency to double group,ie....in a 5 shot string,the first shot was always where it should go...but the others would follow a predictable "high shot/low shot" routine.And groups were about 2 MOA.I suspected I was building a pretty big fire, lots of tourque with that long 175 at high velocity.This occured only with the 175 gr load.139's and 160's did not do this.Apparently I hit the wall with the 175's at full velocity.
Without calling Gene, I pulled the action and cut a small swatch of adhesive-backed pipe insulation;the squishy neoprene-type stuff,and set it an inch back from the forend.This cured things and the first group at 100 yards with the 175 Nosler Partition put 3 shots into 1/2".I then fired it field prone at 300 again and groups went right to 3-3.5",and the "double grouping" disappeared.
I called Gene and told him what happened and he said he doubted the barrel and forend were touching, but likely what I saw was stock resonance;said he had seen that before from light ridgid stocks and slender tubes.Apparently when riding the bags,this is attenuated;but from my hands there was not enough to bring it under control.He was curious about how I came up with the solution,and equally curious about the material used..... :)He said he thought I was on to something....
I have shot the rifle several time since;no shift in POI and good groups. I fired the 160 Nosler Partition and AB at 3150 yesterday at 300 yards;group was about 3" with each; no discernable difference in accuracy from a practical standpoint.Keep in mind this is with my left hand supporting the rifle,and no rear bags.
MM. I dunno because I have not weighed it....but I can tell handling it that it is more than my 7-7.5 pound 270's;less than my M70 Classic in 7RM.I am guessing it at 8-8.25.I also can tell it will not break me down.Not sure I would want it any lighter.
bwinters:I think Brad is right....you gotta be a nut case to build one....
Given all the 7 mags out there,and the STW being pretty much the same thing,it is pretty hard to justify unless you are wedded to the notion that you just want something different, and want to have some fun,while getting a tick up in velocity.Will it matter on anything you shoot?I doubt it...Will it wok really well?We all know the answer to that.....it will work splendidly.Twoof the most prominent riflemen/hunters of the 20th century used it everything from Asian Mountain game,to grizzlies,sheep,elk, moose, etc.gene said he loved that long 175 gr at high velocity,said it would penetrate like crazy..
It is probably as rational as building a 280 AI But hell, the fireform loads do what a 280AI or factory 7RM loads will do,in a rifle configured about the same.....with the Mashburn, that's the warmup
Pretty cool stuff there. I used a 7mm Rem mag with 175's from both Nosler & Sierra for a few years. Really enjoyed that combination, it worked very well for me.
Just a random thought here. Wonder how a 7mm Remington case with a 40 degree Ackley shoulder and long throated for the 160-175 bullet would compare to the Mashburn ballistically?
Just a random thought here. Wonder how a 7mm Remington case with a 40 degree Ackley shoulder and long throated for the 160-175 bullet would compare to the Mashburn ballistically?
Such a setup would make for easier case forming.
That would sound a lot like a 7mm Sharpe & Hart; performance is good, but a tad below the Mashburn, IIRC.
Bob, thanks for sharing your project with us. I have never tried the Mashburn, but I had one of the first 7MM-3000WM in my neck of the woods-1975 or there about. I still use a 7RM some. However, recoil has begun to bother me some and I don't like muzzle brakes or heavy rifles. So my solution to the ideal elk, deer round is the .280AI. I can push the 160gr Nosler Partition at 2950fps without torturing my rifle or cases and recoil is not bad at all. The rifle is on a pre-64 Mod.70 with a #2 Krieger, it's stock is a well finished piece of English walnut with good color contrast and well done checkering. I'm going elk hunting in a couple of weeks so I did a final zero check yesterday and got a slightly less than 4" five shot group at 300yds.
Just a random thought here. Wonder how a 7mm Remington case with a 40 degree Ackley shoulder and long throated for the 160-175 bullet would compare to the Mashburn ballistically?
Such a setup would make for easier case forming.
That would sound a lot like a 7mm Sharpe & Hart; performance is good, but a tad below the Mashburn, IIRC.
MM
Hillbilly: I have not formed an Ackley shoulder,but have "long throated" a few 7RM's and generally they work a lot better than a standard Rem 700-type factory throat.There is not a huge velocity gain,but I found the cartridge a lot more tractible as you got to max than with some shorter factory throats;I think barrels and throats are behind a lot of the difficulties a lot of guys see with the 7RM;why many will hit a wall and the velocities are not quite up to what one "expects" of the cartridge.
Of course if you throat for the 160-175, you compromise bullet/land relationship with 140 gr bullets,because thet have to jump to the lands.Sometimes this works OK and sometimes not.
It is really as much the longer neck,longer bullet seating,and a skosh more capacity that makes it easier to hit these velocities in the Mashburn,as opposed to the Remington...the Mashburn just lets you get there easier near as I can see so far.There is not a real universe of difference;but if you have struggled with the 7RM to get the vels you see from some sources,the Mashburn will be appreciated.
Bob, that Echols stock is a thing of beauty. Makes me want to throw away the edge I just got for my M70
oldelk: That Echols stock is about as nice as I have seen,especially for a magnum chambering;the stock could be one of the reasons it does not seem to kick so much......
Gene tells me D'Arcy did the paint job on it,which is a two-tone black/brown.
DD/Huntr; I will try to get a few pics of the cartridge through the forming process this weekend.
There is more than one way to skin the cat and I have had a couple of conversations with Bill Steigers at BBC;he is instructing me on how to fully form the Mashburn case with tumbling media(corn husks),large pistol primers,and Bullseye pistol powder.
That means I can form cases from new brass by firing out the back door at the house...the neighbors will love it,but hey this is NH...there are always guns going off here!
Just a random thought here. Wonder how a 7mm Remington case with a 40 degree Ackley shoulder and long throated for the 160-175 bullet would compare to the Mashburn ballistically?
Such a setup would make for easier case forming.
That would sound a lot like a 7mm Sharpe & Hart; performance is good, but a tad below the Mashburn, IIRC.
MM
Hillbilly: I have not formed an Ackley shoulder,but have "long throated" a few 7RM's and generally they work a lot better than a standard Rem 700-type factory throat.There is not a huge velocity gain,but I found the cartridge a lot more tractible as you got to max than with some shorter factory throats;I think barrels and throats are behind a lot of the difficulties a lot of guys see with the 7RM;why many will hit a wall and the velocities are not quite up to what one "expects" of the cartridge.
Of course if you throat for the 160-175, you compromise bullet/land relationship with 140 gr bullets,because thet have to jump to the lands.Sometimes this works OK and sometimes not.
It is really as much the longer neck,longer bullet seating,and a skosh more capacity that makes it easier to hit these velocities in the Mashburn,as opposed to the Remington...the Mashburn just lets you get there easier near as I can see so far.There is not a real universe of difference;but if you have struggled with the 7RM to get the vels you see from some sources,the Mashburn will be appreciated.
Thanks for the information. I have never chronographed any 7MM Remington factory ammo that was even close to the factory listed velocity and only one 7mm I have worked with came near the loading manual listed velocities before hitting pressure issues.
This 7MM Mashburn of yours has set me to thinking. That usually winds up costing me money
Very nice rifle Bob. Interesting fix for the stock resonance.
AZ: Th double groups had me puzzled;something changed when I went from the bags to a "softer" medium, like my hands.I repeated the test a few times to make sure it was not me.It wasn't.
Thinking on it I felt the barrel didn't need "up pressure" so much as it needed something to "dampen" vibration,since it had shot well with the lighter bullets.So I thought about the pipe insulation. That cured it.
I have noticed with these precisely tuned sporters with light barrels, that they really shoot well,but equally true that if you feed them something they do not like,they will let you know right away...a guy has to figure out what is wrong.
hillbilly: They are available through D'Arcy at pretty much the same prices for the stock as for the mcMillans IIRC. A friend bought three,and sent them to CAS for paint and bedding.
hillbilly: They are available through D'Arcy at pretty much the same prices for the stock as for the mcMillans IIRC. A friend bought three,and sent them to CAS for paint and bedding.
Thanks. I didn't know if they were more expensive than the standard ones.
Hmm.....never heard about the round could someone tell me a bit about it..
Dober
Dober you walked me through this project....thanks! I have mostly not shot anything else since it showed up!This thing is almost the most fun you can have standing up
BTW, I tried the FF method Steigers and RinB schooled me on....result is perfectly formed Mashburn brass,which I loaded with 75-H1000 and 160 Partition.Going to the range with it now.
7mm Mashburn's are for complete nut-jobs. I should know, I'm friend's with one... (grin).
BTW, beautiful rifle Bob!
Thanks, Brad.Handsome is as handsome does and near as I can tell so far it performs nicely.Being a rifle "student"(always learning),and a bit of a history buff,it's an interesting cartridge to me and fascinating when you think about how it got started....and how well it turned out in a day when folks did not have access to the info and technology that we now have;even Warren Page had to send cartridges and rifle to Remington to get the velocity info that any of us can get in an afternoon now,on our own.
Tastes in cartridges shift like the wind and guys are constantly running around to newer,different cartridges.I think a lot of this activity is circular, like fish swimming in a barrel,and lots of new cartridges are not all that "new";the design or performance parameters having been set decades ago.The Mashburn is a good example of that....witness the "new" 284 Jarrett,or the STW.
Goes to show you can't really know where you are unless you know where you've been.....
I thought it was poetic justice that my first shot over the chronograph with a 175 Partition measured 3050.....precisely what Page said his old rifle did at the Remington plant back in 1959....
And yet there is newer good stuff today.....personally I think the 6XC should replace the 243 in short action sporting rifles....just a better, forward looking design.And old Bill Steigers told me the other day if he were looking to build a hotter 375 than the H&H round,he would not bother with his old favorite 375AI,but would move right on up to the 375 RUM with its' good, modern brass and plenty of capacity..
.....this from a guy whose clients were blowing out 404 Jeffrey brass and necking it down to 30 caliber a couple of decades before the 300RUM saw the light of day...interesting to think about and there ain't much new under the sun!
Your Mashburn would turn 120g GS-HVs into screaming missiles of destruction. It would work just fine Bob. They also have a 140g GS-HV but im not sure that your 1-9 twisted barrel would do the trick. Person would have to call. The lighter bullets dont seem to be theme here in this project. Betcha a 120 grainer wouldn't kick as much as the stuff your shooting.......
http://www.gsgroup.co.za/284140HV189.html A bit confusing. Gina could clear that up in no time. The 140 HV should work fine. As monos they are long for caliber. .... A 140 HV out a a Mashburn......
Left to right is a 7 Rem Mag empty;a 300 Win Mag after a pass through the Mashburn form die which starts to form the shoulder and lengthen the neck;a Mashburn case afer a pass through the trim die,which brings the neck to 7mm; a loaded 7RM round; Mashburn case loaded with the 175 gr Nosler Partition.
Guy how did the Sierra's do for you?Kill game with them? I have a pile of them.
Bob,
I have killed a pile of deer sized citters with 160 Sierra Gamekings in a long throated 7mm Rem Mag using max loads of R22. This is a pretty tough bullet and it pretty much exists every time. I substituted it for a 160 Nosler Partition for use on paper and later tried it on game. Frankly,I never could tell them apart,quick kills and exits.
John Barsness uses the same bullet in his 7x57 and speaks well of it.
I also used the 150 Sierra Gameking out of my Custom 7mm Weatherby for long range deer and antelope. It has worked well at what I consider long range,350 to 500 yards. So far nothing has walked away from one of these either.
Yes it is Britt;thanks for that. I have been burning Partitions to get to a hunting load,but if that Sierra works I may run those....got several boxes.
Mike as you know,about everything in 7mm works good in a big 7,provided bullet structure is suited to the task.This leads to a lot of jumping around One bullet for a bunch of tasks has its' appeal.I have used the 140 and 160 a good deal in the past,but not the 175.
I won't stick strictly to the 175(I'm taking 160's to Wyoming),but keep in mind that it certainly has a lot going for it....a high BC,noted for deep penetration,reliable expansion,and suited to anything you can use a 7mm on.
Plus this cartridge(in truth most all 7 mags) starts it fast enough to qualify it for long range(at least my brand of long range)on about anything.....its' trajectory started at 3050 matches pretty closely to that of a 300 Weatherby 180 Partition started at 3150-3200 or so.Flat shooting and hard hitting enough for any rational purpose and still manageable.
I also have a bunch of 160 and 175 BBC's that I will use.And none of this prevents me from using a TSX,etc. I even have a box of 150 Etips downstairs
Bob, I havn't had much luck with accuracy from 175's in my 7 mm barrels. I use to load 175 Sierra and Hornady for my brother's Savage 110 and it loved them. It didn't make sense to me because his rifle had a 1-10 twist, which proves you never know until you start shooting the loads.
When I was a youngster in my 30's there was an older gentlemen in camp that had a Rem 700 and he shot 175 grainers for everything from elk to antelope. He had it zeroed at some long distance like 500 or 600 yards and just aimed a few inches lower on the animal at everything closer. Another thing that didn't make much sense to me at the time, but he was used to it and it worked for him.
Dober I got a funny feeling that even in this day of super bullets, that old 175 might just be one of the superest of all.
That thing is as long as a panatella!
StrayDog; I struggled a bit with the 175,too in the 9twist barrel....until I figured what was going on...but they are shooting fine now,and this rifle puts them right there with the 160's at 300 yards.I could use them pretty much interchangeably.
There is only about 100 fps difference in the velocity between the two......so a guy scratches his head and says..."Geez,why do I need anything but the 175?"
I have heard of the 7 MM Mashburn Magnum, and also a 7 MM Mashburn Super Magnum.
Are they the same cartridges?
I have a Speer Reloading Manual for Wildcat Cartridges, dated 1960. It has 7 MM Mashburn Magnum loads listed. This is where I got the Mashburn Magnum and Mashburn Super Magnum. In one place it is called the Mashburn Magnum, and a page or two futher on, it is referred to as the Mashburn Super Magnum. I have always wondered if they were both the same cartridge.
I used the 175 partitions on a variety of game in Namibia last year and they produced the nastiest looking wounds I have seen. You have to go to 375 to notice a consistent difference. I was shooting them at about 2900 and at 3050 they would only be better and flatter shooting as well. Reminds me of an old girlfriend who said "I am a sure thing and don't take advantage of it". Still have the big 7 but was stupid re the girl.
Congrats on the new rifle! Hope is it all that you expected and more!
I assume as it uses D'Arcy's mag box that it holds 4 down? How do you like D'Arcy's Legend stock? I am thinking about ordering one for a similar project.
I think it's reasonable to say we could use a few more pics of the rifle and perhaps a pic or two of the Mizzum round would be nice....and maybe a recently dead critter and the new rifle...?
Guys I will do the best I can on more pics....and hopefully if I find the Wyoming buck I'm looking for I can get a dead critter .....I just got the rifle two weeks ago.
Dave there are pics of the cartridge that Skane posted.
123: I have read that Mashburn worked on at least two versions;a H&H length case necked down,and a slightly shortened version that was more efficient,and which he called the 7mm Mashburn Super.This is Dobers cartridge,and the same one used by Hagel and Page. It is the cartridge my rifle is chambered for.
Hagel writes that there was a 3rd one, which seems to have been a "short" version,which I guess no one liked either. It was the middle one,the one we are talking of here,that became the "Super".This was the one that is variously refered to as the Mashburn, or Mashburn Super.
Bob, good luck on finding that big buck. If you do get him, pictures please. One of my brothers is in Evanston now he'll be hunting soon, he too is on the trail of a big one. I'll join him later in the month in Utah when we'll be hunting elk and deer. In September I got a decent buck antelope just a mile or two or three from Evanston, but in Utah. As you can likely tell I'm ready, really ready to go.
This thread has me lusting after another big 7mm. A 7 Ultra on a model 70 is appealing and it would fill the niche between my 300 ultra and 280,270 and 25-06......
Gonna rock a Big 7 one of these days. I kind of wisht I'd listened to you and Dober and done my Sendero as a 7mm, but if memory serves they only offered it in the 7 RUM at the time which just REEKS of "overbore"......
Thanks Jeff!Well you could get a PacNor or something for your 300 and rebarrel....like falling off a log!That would be very simple.
That 7RUM is quite a cartridge,fastest of the bunch, but will likely chew up barrels pretty quick....but it works!
Yeah, that's the plan. As you know it won't break my heart to consign the tube on it now to the scrap heap of history (though it is accurate).
The 7's are interesting. The difference between what my loading books say, and what people claim, is pretty dramatic for say the 7mm Mag. From there, there the fire-breathers like the STW and the RUM. I guess what you are saying is that the mizzum fits nicely in between.
I can't like a forming step with the brass though. I essentially have to do that with my 300 WM and annoys the hell out me.
Jeff the form load is fun....doesn't kick at all and is accurate as Dober says.Forming brass is pretty cool too!It really is an easy cartridge to work with; no surprises, gets the advertised velocity and does not kick bad at all......
I don't like wasting components. It adds a box of primers, 50 bullets, and 1/3 lb of powder to the cost of 50 pieces of new brass!
Getting to know a new rifle, not so bad, but as an ongoing thing it annoys me with my rifle anyway.
(mine has a very sloppy chamber, won't shoot well with virgin brass, to top it off I only get ~4 maybe 5 loadings before the necks split out so to even get THAT, I have to anneal, then form, THEN finally have usable brass.)
The Speer manual I mentioned in my first post has several loads listed for the 7 MM Mashburn, with different weight bullets.
The book was publishd in 1960, so I don't know how up-to-date the data is, but if you want, I can send some of the loads, if you don't already have them.
I enjoy comparing the old powders to the newer ones' and how they all performed.
For now, I am pretty well set for loads,and it has boiled down to: 160 Partition-75 H1000-3150 fps 175 partition- 73 H1000-3050 160 Bitterroot-74-H1000 for the sam vels as the 160 partition. 139 Hornady-65-IMR4350. This is Dober's fireform load and gives 3150-3190 from my barrel.
I also worked up a "form load"using large pistol primers, Bullseye,and RCBS corn husk tumbling media. This works great as well.
What is interesting is that Warren Page's load for the 175 was 73 of the WW II H4831 and the 175 partition at 3050;same velocity and same charge weight I got with H1000.
Hammerdown I did get that buck in Wyoming...he grossed about 180. He was a nice one!
But I did not get him with the Mashburn.
Day before departure I went to the range and had a scope issue. Metering hours before departure,I grabbed a 270 that was zeroed.Shot the buck as he ran about 80 yards after a long stalk.
Did use the Mashburn back here on a buck at about 300 yards later that same year.I do expect to use the rifle this fall again.
As to the build if you are inclined, no need to get fancy. Sgt Beretz on here punched out a M70 and we walked him into a knot-hole load (factory barrel), in two afternoons. Dave 7mm built one with a Rem 700 and Chanlyn barrel and was done with his ladder test in one day.
Hi Bob, That Chanlyn barrel is a sweethart. No 3 conture is drilling stupid small groups at 400 yards with 168g Berger classic hunting bullets.I sent Bob the pictures... My Mashburn is just a tool.Built the way I like. M700 action McMillian HTG in edge painted in desert digital camo. Worked over M700 trigger.Safe locks the bolt down. Feeds and functions like glass.. Even skipped the S&B and put a Zeiss Victory 2.5-10x50 to keep the weight off it. The first season I ran Rel 25 and the 150g ballistic tip. Deer ran aways more than I wanted.Dead deer running type of thing. Last season switched to the 168g Berger.And H1000. Dead deer.No problem. I like H1000 alot. Thanks for all your help Bob.
I like mine so far. Done everything I asked of it.
Worked as it was was supposed on the lil cow..
160 AB blew in and out the other side at 254 yards. She never took a step. Not a manly test of it, but it was cool to finally put all the shooting on something.
Well Bob, how long before you begin tinkering with a 28 Nosler?
Reloader the 28 Nosler sounds like a great cartridge.
But I don't see one in my future. I am so vested in 7RM and 7mm Mashburn rifles, brass,dies etc. that whatever advantage it may offer will be lost on me.
I am up the whazoo in 300 Win Mag brass to form cases and the Mashburn Super has proved to be pretty simple to make and run that I have no real desire for anything else.I am very happy with the cartridge and my rifle.
Doesn't the new 28 Nosler have quite a bit more powder capacity than the Mashpotato ? Isn't the Mashburn just a 300 WM case ?
It does.
I just checked the Nosler site.
28 Nosler with 175 gr. bullet, 90 gr. H20 case capacity 300 WM with 175/180 gr. bullet, 82.3 gr. " 300 Wby with the same bullet 91.8 gr. "
I remembered that the 6.5/300 Wby was pretty close to the 26 Nos, although the new Wby round is hotter. Slightly more case capacity plus Roy's magic freebore...
Using the .300 WM as a basis, the 28 Nos is a bigger round than the 7mm Mizzum.
Bob may be able to educate us on the exact case capacity of the Mashburn with 175 gr. bullet.
DF I am certain the 28 Nosler holds more powder. I never measured case water capacity with a bullet seated but the case itself hold 90 gr of water to the top of the neck.There will be tiny differences based on brass internal construction, thickness, etc etc.
(Not that it matters a whole lot but it might be more accurate to say that the 300 Win Mag is nothing more than a 7mm Mashburn Super necked up,and with a shorter neck since (a) the Mashburn came first; and (b)both cartridges share a similar case length, the only two belted cases i know of with that case length.This has made me wonder where Winchester came up with that case length. Maybe some WW engineer saw a Mashburn.?..)
Neither here nor there but good to understand the timeline of how we got where we "were"....
Velocities are as interesting as case capacity and here's what I've seen from the Mashburn,and this includes my rifle and a few belonging to others. Barrels are 24" unless otherwise indicated:
My rifle: 175-73 gr H1000 for 3075. 160/162- 75.5 gr H1000 for 3200 (loads with Retumbo and RL25 boost this to 3250 without a sweat and good case life.
I have not fed mine any bullet lighter than 160 in full Mashburn loads, but my FF load (to make brass) with 139 Hornady -65 IMR4350- gives 3150-3190;about like a 280AI.
These velocities are about identical to the velocities obtained by my buddy,and by Scotty Beretz on here, from their rifles. The loads are so uniformly similar, rifle to rifle,that we could shoot each other's loads.
Dave 7mm uses the 150 BT at somewhere between 3250-3300 fps in his Mashburn Super. Dober uses the same load in his. Laker on here has one and shoots the 150 BT but don't recall his velocity and don't know what his loads are.
RCamuglia on here uses the new 195 gr Berger at (IIRC) 2965 with 72 gr H1000 from a 28" barrel,from his 7mm Mashburn Super. I know Rick has run his to over 1500 yards and is happy with it.
I'm in close contact with most all these guys,and they reported as they did load work up.
In any event these velocities are substantial enough that I am not going to worry about how much the 28 Nosler beats it. I'm also not paying much for brass since I'm using that common 300 Win Mag stuff.
Besides, doing all these cartridge comparisons gives a guy a headache. I'll just stick with what i got...
The way Rcamuglia runs his .264 WM, he's nipping at the heels of the 26 Nos and with less case capacity. He's using RL-33 instead of 869 or 872 like I use in my 26. I'm burning a good bit more powder for only marginal gains over his top loads. I know, I know, case capacity rules but there are limits on how much one can squeeze out of a round. Some accuse him of running excessive pressure, but he seems to know what he's doing. I've pushed the 26 to pressure signs without that much gain in performance.
It seems to me, as overbore capacity increases, efficiency drops and reloading for top performance in some of those mega rounds can become a challenge. Data I've seen from even bigger 6.5's isn't as impressive as case capacity would indicate. The new 6.5 Wby edges the 26 Nos by a little, burning more powder and using freebore. The 6.5 RUM and STW are more examples of diminishing returns, IMO.
I know 7 mm's with similar case capacities aren't as overbore as 6.5's and probably not as finicky.
I noted all that to say, the 28 Nosler premium in performance over the 7 mm Mizzum comes at a price some may be unwilling to pay. I can't argue with that...
Both are experienced hand loaders and match shooters and whistled through case forming,finding pressure, and "nodes" at distance so fast it made my head spin. They both demonstrated how easy it can be. As I recall both were mostly "done"in 2-3 range sessions. These boys don't screw around.
Rick taught me something when he bumped into a case problem which he solved quickly. Done.
I never recommend the round because it's a wildcat;most people are turned off by making cases. Understood. They are far better off with a factory offering.There are plenty of good high capacity 7mm's out there, the Nosler among them. No need to wildcat a Mashburn.
But if you do, it'll perform well against any of them.
My main point, bigger isn't automatically better, or more of these mammoth, overbore rounds would have caught on, which they haven't.
Efficiency, at least to me, is a big deal. Diminishing returns are just that, diminishing returns...
Balance is a big deal, at least for me.
I think the 26 Nosler is on the edge and for sure the new 6.5/300 Wby. I find myself working more with my 6.5-284 and 6.5 Creedmoor. I still like the 26, just have other projects ongoing that do what I need them to do. I don't have to burn 90 gr. of powder every time I shoot something...
My 6.5 stories are off the 7 mm topic, used as examples of what I'm seeing.
Tested a 28 Nosler a couple months ago. Didn't have time to test a zillion powders and bullets, but did test a few, and the best load was 160 at just under 3350 fps, using published data with Norma 217. That's from a 26" barrel.
There were zero "pressure signs" but I am sure the load could have been pushed some more without encountering any, since SAAMI maximum pressure is 65,000 PSI and pressure signs don't usually start showing up until around 70,000.
Tested a 28 Nosler a couple months ago. Didn't have time to test a zillion powders and bullets, but did test a few, and the best load was 160 at just under 3350 fps, using published data with Norma 217. That's from a 26" barrel.
Tested a 28 Nosler a couple months ago....and the best load was 160 at just under 3350 fps...
Granted, it is fast.
What do you reckon Nosler's "flat out, lights out" Herd Bull MPBR is advertised at?
Don't know how Nosler measures PBR,but probably so close to the 26 Nosler you'd be hard pressed to tell the difference.
I just ran the quick and dirty numbers through a ballistics calculated, with the 160 AB at 3350. From a 300 yard zero the drop at 400 yards is 7.8"; 13.5 at 450,and 20.6 at 500. That's "flat" for a BG rifle and bullet.
In comparison I ran the numbers for the Mashburn with the same bullet at 3200 ( I would call 3250 as top end). From a 300 yard zero the Mashburn drops 8.6 at 400; 14.9 at 450,and 22.8 at 500.
We can play with vital area numbers and come to our own conclusions. The differences exist but are not great.
Keep in mind the Nosler numbers are from a 26" barrel and the Mashburn a 24".
I bet if we fed the Mashburn a 162 Amax there would be no difference at all....but we won't go there. Just a thought.
To be honest I was thinking that 28 Nosler would match up well with the real heavy 7mm bullets,say nothing less than the 160's 162's...the 175-180's...maybe even the 195 Berger if you're inclined that way.
The case has the capacity to really drive those heavy bullets and I think that's where the advantage is.
Anyway that's how I'd go today. I shoot the 162 Amax a lot in the Mashburn but have yet to use anything less than 160 in that case.
Makes sense. Reason I asked was because the 150 gr LRAB has a higher BC than the 160 gr AB. The 168 gr LRAB's BC is off the charts. I'll bet that you can drive them faster due to the shorter bearing surface on the LRAB's.
RD: That case has enough capacity to drive any 7mm bullet fast!
And the heavies will outpace the lighter stuff at distance. It's a long range cartridge. Might as well take advantage of all that capacity.
My own half-assed rule is that if a cartridge will drive bullets substantially over 3200 fps, I figure I will reach for the next size up. But that's just me.
Lately,if I want to know if a magnum capacity 7mm shoots well, the 162 Amax is the first bullet I grab to try. I have never killed anything with them, but to 600 yards(as far as I can shoot here regularly), it out paces everything else that I have tried.
But that's the beauty of those LRAB in that you can run either the 150 or 168 LRAB and still have super high BC's and drive em fast too. I'm a deer hunter so I wouldn't need to use a heavier bullet than either one of those. Might be a little less recoil too using the lighter slugs. One of the loads on Noslers Load Data site calls for 78 or 79 grs of IMR-7828ssc that will drive those 150's at over 3300 fps whereas a lot of the other loads that get top velocities are using 90+ grs of powder. More muzzle blast, throat wear and barrel wear I'd imagine pushing 90+ grs of powder every time you launch a slug down the tube. The standard 160 gr Accubond has a BC of .531. The 168 gr LRAB has a BC of .652 which I believe is higher than the (162) AMAX's. If I were chasing down Elk, I rather be using an Accubond over an AMAX.
Put my 7mm Mashburn Super Magnum (AKA 7 Mashengruber :D) together on an A-Bolt LA. Bartlein light Palma 9 twist 5R. Just bedded it into the factory stock whilst I wait for my McMillan A3-5 to show up. Leupold Mark 4 8.5-25 LR/ERT that was hanging around, EGR 20 MOA rail and TPS rings
Yes. Run them through the 7mm Mashburn sizing die (I used a Redding Type S FL Bushing Sizer)
Next, either load bullets like BobinNH does to fire form, or use the Cream of Wheat method like I did to save barrel wear. After the COW method, my shoulders were still .004" short of fully formed.
Went into development at that point. I would definitely turn the necks after they are fully formed into the shoulder like you see there to eliminate any chance of a donut forming....
Anybody care to email me a drawing on the specs of the reamer you are using? I want to order one and dang sure want it to be "right". Send me a PM if you have access to one. Thanks in advance
7mm Remington Magnum ..........73.5 gr. 7mm Weatherby Magnum ..........78.0 gr. 284 Jarrett ...................85.5 gr. 7mm STW .......................98.3 gr.
The case capacity of my Mashbrun cases are about 4.5 gr. more than the Weatherby. These are case capacities to the base of the neck. From my experience with the Mashbun,it and the Jarret look to be the same or close at least in case capacity if not in form.
Per recent articles, the Nosler has a capacity of 99 grains of water.
Fully formed Mashburn cases (mine) held 90 gr H2O to top of neck.
As Docbill points out the Mashburn case has a longer neck than a 300 WM case. It is also very slightly more blown out than the 300 Win Mag. Helpful with long 7mm bullets in a 3.6" box(aka all Rem 700 actions;M70's can also be easily altered).
The Jarrett is based on the 300 Win Mag case as well. He purloined the Mashburn idea. He's just behind the times by a few decades....
Put my 7mm Mashburn Super Magnum (AKA 7 Mashengruber :D) together on an A-Bolt LA. Bartlein light Palma 9 twist 5R. Just bedded it into the factory stock whilst I wait for my McMillan A3-5 to show up. Leupold Mark 4 8.5-25 LR/ERT that was hanging around, EGR 20 MOA rail and TPS rings
Put my 7mm Mashburn Super Magnum (AKA 7 Mashengruber :D) together on an A-Bolt LA. Bartlein light Palma 9 twist 5R. Just bedded it into the factory stock whilst I wait for my McMillan A3-5 to show up. Leupold Mark 4 8.5-25 LR/ERT that was hanging around, EGR 20 MOA rail and TPS rings
That is definitely the most contemporary looking Mashburn I have ever seen! It's a long ways from Page's Old Betsy, but I bet it reaches farther than Warren ever dreamed .
Anyone got a picture of Old betsy for contrast to Rick's rifle?
Thanks to Doc Bill for the pictures of Old Betsy and Scotty for posting.
Thought it would make an interesting contrast to Rick's new rifle, being as they are both chambered for the same 60+ year old cartridge.
Back then, Page used the "best" technology of the day for close to (over?) 400 head of BG animals world wide with this rifle,and the 175 gr Nosler semi spitzer Partition,started at 3050 fps with 73gr H4831...and out to 600 yards on a couple of head of game,as I recall a Greater Kudu and a Wyoming bull elk. Scope is a 4X Kollmorgen Bear Cub.
In contrast, and today, Rick is running a 195 Berger with H1000 at over 2900 fps,and shooting out to 1500 yards with the same cartridge, modern scope,and modern bullets. Distances Page would have thought impossible no doubt. Interesting that it still keeps pace with about anything considered current and up to date among long range cartridges,even if it is a wildcat.
Sounds like a wildcat that has stayed with the times....ample evidence that Art Mashburn did his homework,and Page knew a good thing when he saw it.
Maybe, as Doc Bill said, the best BG wildcat that never became a factory adopted cartridge. Which is OK,too because we can still use it today.
Rick you only have 399 animals to go with that rifle!
I mean, who doesn't like a good 7-MM or two or three. I guy can never have too many.
Totally agree with that. The only problem with having 1 Mashburn is it makes me wanna have a 2nd one just in case...
It has been an awesome cartridge to work with. Mine is an old beat up 70 XTR that was rechambered to 7 MSM.. It shoots pretty danged well as is and hunts fine, but a truly nice 7mm MSM is high on the want list.
In contrast, and today, Rick is running a 195 Berger with H1000 at over 2900 fps,and shooting out to 1500 yards with the same cartridge, modern scope,and modern bullets. Distances Page would have thought impossible no doubt. Interesting that it still keeps pace with about anything considered current and up to date among long range cartridges,even if it is a wildcat.
The only reason I stopped at 1571 yards that day was because it was the longest target we had set up for which I had scope travel
The Mark 4 only had a 30mm tube. The new Mark 4 should get me to well over a mile. The ballistics of the 195 grain Berger at 2970 are better than the .338 Lapua shooting a 300 grainer.
Hey Beretzs,
I hear you're using RL-33 with the 175's and doing well. I might have to try some with the 195, but it's shooting so well with H-1000 I'm afraid to try! 100 more FPS may or may not be worth it...
In contrast, and today, Rick is running a 195 Berger with H1000 at over 2900 fps,and shooting out to 1500 yards with the same cartridge, modern scope,and modern bullets. Distances Page would have thought impossible no doubt. Interesting that it still keeps pace with about anything considered current and up to date among long range cartridges,even if it is a wildcat.
The only reason I stopped at 1571 yards that day was because it was the longest target we had set up for which I had scope travel
The Mark 4 only had a 30mm tube. The new Mark 4 should get me to well over a mile. The ballistics of the 195 grain Berger at 2970 are better than the .338 Lapua shooting a 300 grainer.
Hey Beretzs,
I hear you're using RL-33 with the 175's and doing well. I might have to try some with the 195, but it's shooting so well with H-1000 I'm afraid to try! 100 more FPS may or may not be worth it...
That's impressive regarding the 338 Lapua. A lot of return for the recoil dished out.
In contrast, and today, Rick is running a 195 Berger with H1000 at over 2900 fps,and shooting out to 1500 yards with the same cartridge, modern scope,and modern bullets. Distances Page would have thought impossible no doubt. Interesting that it still keeps pace with about anything considered current and up to date among long range cartridges,even if it is a wildcat.
The only reason I stopped at 1571 yards that day was because it was the longest target we had set up for which I had scope travel
The Mark 4 only had a 30mm tube. The new Mark 4 should get me to well over a mile. The ballistics of the 195 grain Berger at 2970 are better than the .338 Lapua shooting a 300 grainer.
Hey Beretzs,
I hear you're using RL-33 with the 175's and doing well. I might have to try some with the 195, but it's shooting so well with H-1000 I'm afraid to try! 100 more FPS may or may not be worth it...
How long a barrel you got on the 7mm ?
if you run the numbers thru JBM , I get ......
7mm drop @ 1000 yds 23 MOA , drift @ 10 mph 48.7 MOA , 1458 ft lb energy
338 drop 25.4 MOA , drift 48.5 MOA , 2102 ft lb energy
I used 2800 fps in the 338 with the Berger 300 gr elite hunter , doable in a 26 barrel
it looks to me like the 7 wins ever so slightly in trajectory , the 338 shades for wind drift , and the 338 simply crushes the 7 in energy delivery , which you would expect.....
so what makes the 7mm ballistics *better* than the 338 ?
Point is well made by comparison. The Mashburn with these high BC bullets is an impressive, modern performer,and the performance comes with substantially less recoil than a 30 caliber or 338 with the same flight characteristics.And with bullets heavy enough to be reliable on most any open country animal.
That it "suits" in a 60 year old lightweight Mauser,or a specialized,modern LR rig demonstrates its adaptability.
Sure...with a price in recoil. That they may "hit harder", to the extent we can quantify that,is because its bullets are heavier. That makes sense.
But cranking those equivalent 30 caliber bullets up to the same speeds as the equivalent 7mm(to get the same flight characteristics for sure hits in open country),and we find we need a bigger case holding substantially more powder.
Take a simple example of the 300 Weatherby. It takes 83-87 gr of H1000 or 7828(two good powders for the 300 Weatherby) to move a 200 gr partition or AB at over 3000 fps from a 26" barrel.
OTOH, the Mashburn starts a 175 gr Partition at 3050-3100 fps with 73-74 gr of H1000 (similar BC's and velocity).
No doubt the 300 will boot you more in an 8.5 pound rifle.
A buddy took his Mashburn to Wyoming for two seasons, killed a couple of big mule deer with the 175 Partition. He said it killed like his 300 Weatherby. I told him compare a 180 gr 30 caliber bullet at 3200 fps,to a 175 gr 7mm started at 3100 fps. That tells you part of the story.
Even Elmer Keith noticed it back in the 30's with the DuBiel 7mm magnum with 180 WT&C bullet vs the 300 H&H.....
In case we have't noticed, heavy 7mm bullets nudge squarely into the middle range of 30 caliber bullets. No wonder they kill convincingly. The rash of new 7mm is ample evidence that lots of people notice this.
Bob , I concede the point that 7mm is very efficient....
what I maybe dont concede is that a Mashburn can kick all that much different than a 300
when you are running nearly 200 gr of bullet at nearly 3000 fps , you are certainly in 300 weatherby territory
I dont know what powder is being used to push those 195 gr pills , maybe RL 33 ? , but I bet its slow and takes nearly as much as a 300 weatherby charge
thus it seems to me it is gonna kick alot like a 300
pushing 175s in the Mashburn at 3 t0 3100 is surely neck and neck with the 300 winchester.....
sd: This business of the Mashburn kicking less than the 300 magnum was pitched in the days she the 300 Weatherby was cock of the walk and the 300 Win Mag did not even exist.
A better way to say this might be that...you get kicked less for the same level of external ballistic performance. That sound fair?
I can tell you that I have shot a lot of top end 300 WM,300 Weatherby, and 7 Mash burn. We frequently shoot 300 Bee and Mashburn side by side as my pal has both.
I joke with him and say "Which would you rather shoot?"
Answer: "The Mashburn".
And, "Which would you rather carry up an elk mountain?"
Answer: "The Mashburn".... It's about a pound lighter.
I can't quantify this in words any better than anyone would see shooting the two side by side. Mashburn recoil is fast...but lighter than a 300 win or weatherby. My rifle weighs 7.5# scoped,and I am a whimpy old man....I cannot manage a 7.5 pound 300 win mag or Weatherby.
Keep in mind that Rick is only burning 73-74 gr of H1000 to generate those velocities with a 195. How much powder and bullet would we need in 30 caliber to get the same level of performance. I suspect we will get kicked a lot more doing it.
Ok just for giggles I ran some data thru the RCBS recoil calculator. Both theoretical guns weight 7.5 lbs, bullets 175 gr for 7 mm MSM., 180 for 300 Roy. I used my own load data, and Nosler for the Roy. My MSM uses 73 gr H1000 the Roy used 85 of several H1000, 7828, RL-25 for similar vel.; 3050-3100 fps.
Recoil for the MSM was 34 and the Roy 38 ft lbs.
I regularly shoot my 7.5 lb. MSM and it doesn't seem to be vicous or unpleasant. YMMV.
4 ft lbs difference.....I just dont think my kick o meter is good enough to detect that difference in a side by side blindfold test.....certainly stocking and fit of the rifle to an individual will make much more difference than 4 ft lbs
I suspect most of ya all that are finding Mashburn recoil alot different are using lighter bullets than 175 to 195
a load ive used alot in 300 roy is about 76 gr 4350 under 180s....so size of the powder charge doesnt always have to be much different
I do think the Mashburn is best of the breed if you want a 7 mag....just enough powder capacity to get what the 7 Rem mag users wanted all along without going to the ridiculous powder appetites of the STW or RUM
sd: I do shoot mostly 160's...with a smidge of 175's tossed in. I have never fired 195's.
I can say that I have fired enough Mashburn and 300 Weatherby to notice a difference.Mostly because I have shot them side by side....same day....and of course I am not implying the Mashburn does not recoil at all, because of course....it does.
It's accuracy load is a Barnes 175 LRX and 64 grains of RL17 for just a hair under 3,100.
This load in a light recoiling light rifle matches up pretty good to the Mizzum shooting 175 Partitons.
Their bullet BC's and velocity are the same. 64 grain load in the Wizzum might have less recoil. The LRX performs like a BBC from my test in dry print if that means anything and penetrates as well if not better than a Partition.
One reason I have a 7mm Mashburn is a big supply of Bitterroots. smile
That is a very qualified reason!
Nothing out-penetrated the 175 BBC. My notes say it penetrated 12" in dry print.
(Have not tested the 30/175 LRX yet, but did test the 28/145)
On a side note, I shot a good sized Mule Deer buck this past fall with a Sierra 7mm 175 Game King. At 580 yards it hit at an angled chest shot, penetrated and exited even going through some full stomach. Buck went about 50 yards after being hit and dropped.
This field result confirmed to me that those dry paper test are a fairly good means to judge a bullet as the Sierra was only a 1/2" behind the Partition (9") in the test.
I had Leupold make me up a CDS dial for that Sierra load. I know it will work.
I hear you're using RL-33 with the 175's and doing well. I might have to try some with the 195, but it's shooting so well with H-1000 I'm afraid to try! 100 more FPS may or may not be worth it...
I'm in the same boat. Have a great load that runs the 175 PTs at 3050 from my 24" rifle with 73-74 grains of H1000 depending on the lot. It's very accurate and seems consistent.
Same for 160's and H1000. Guilty accurate as well.
I happened to grab a couple of pounds of RL33 to try. Getting 3100 from RL33 with the 175's but I'm not sold it'll be worth the effort honestly. It's just a rechambered M70 so there's only so much life in this barrel.
On the recoil deal. I'll shoot 175s all day long. 200's from my 300 WBY are a whole nother animal.
Ok Beretzs, ran your 200 gr bullet 300 Roy using the above 7.5 lb rifle, and 84 gr powder from the Nosler load book with 3050 fps. and the recoil is 42 ft. lbs.
That's about like my .416. I don't imaginge that there are many 7.5 lbs. 300 Roys out there but we have to use something for comparison.
my mashburn likes the 150 grain class of bullets as well as all of the tsx slugs.
My two favorite powders are 7828 and norma mrp
federal case 150 swift s2 69.5 grains mrp federal magnum match primer. runs about 3185 from a bored out Remington 700. Has run .5 moa out to 400 which is the furthest that I've run it.
federal case 150 grain ballistic tip 71 grains 7828. federal standard primer. 3220 .75 MOA to 400
I had more trouble getting velocity from the 160s and 175s. It might just be my barrel though. I have a 1 in 9 twisted bartlein sitting here for when it goes. I hope that the 5r rifling doesn't cause any problems. I'd like to talk to that cover guy sometime.
I had more trouble getting velocity from the 160s and 175s. It might just be my barrel though. I have a 1 in 9 twisted bartlein sitting here for when it goes. I hope that the 5r rifling doesn't cause any problems. I'd like to talk to that cover guy sometime.
79: 160's and up is where 7mm magnums start to get stubborn,due to the fact they are heavy and more bearing surface. But mostly I've had little to no difficulty with 160-175's. My barrel is a Krieger. No problem with velocities of 3200-3250 with 160's,and 3050-3075 with 175's and H1000, RL25, etc.
If yours is a Rem 700 barrel I have noticed they tend to run on the slow side,although that's not universally true.Just a trend we noticed comparing my friends Rem 700's in different calibers to my Kriegers and M70's.
I think your Bartlein will be very good with no issues. Gene Simillion just got one in for my friend's Mashburn and is building another for a second friend, both on Bartlein barrels.
What are the options for 7 Mashburn dies? Is RCBS the only game in town and what do they get for a set? I missed a set on ebay that went for $33 because I wasn't there to bid :-(.
Does anyone rent this reamer and if not, is there a smith with one that would long chamber a barrel that I would finish? I'd prefer to do everything myself but the parts for this caliber are not generally available. Buying a new one is an option as well.
What are the options for 7 Mashburn dies? Is RCBS the only game in town and what do they get for a set? I missed a set on ebay that went for $33 because I wasn't there to bid :-(.
Does anyone rent this reamer and if not, is there a smith with one that would long chamber a barrel that I would finish? I'd prefer to do everything myself but the parts for this caliber are not generally available. Buying a new one is an option as well.
gzig: Dies are made by RCBS and have been for quite some time,although they tend today to be a special order whereas a few years ago they were on the shelf. Nevertheless they can be had in a few weeks.
RCBS makes not only the FL die set, but also the Form/Trim dies for forming brass.
My friend and I sent fired cases to Redding to have dies made,and Redding had never made them so I guess ours were the first sets they made.
For forming cases from 300 Win Mag, Redding did not feel a F/T die was required,the FL die being sufficient for initial case forming. Guess I can't argue with that, but I still use my F/T dies. I've done it both ways.
The cost for dies from either source is about $150 bucks last time I checked.
As to reamers I know there are smiths out there who could do a barrel. Gene Simillion built mine,and has a reamer and I think he'd be happy to chamber a barrel. I know Dave7mm on here had his smith do a rifle. Dave's smith has the reamer but I don't know who he is.
I had more trouble getting velocity from the 160s and 175s. It might just be my barrel though. I have a 1 in 9 twisted bartlein sitting here for when it goes. I hope that the 5r rifling doesn't cause any problems. I'd like to talk to that cover guy sometime.
What was your trouble? Pressure signs before you hit the speeds you wanted or something different?
3200 with H1000 and 160 AB&160 PTs seemed very easy in my rechambered Winchester barrel, but understand all barrels are different.
I couldn't get within 3 grains of loads with the 160 grainers that other guys were running. It's okay though half moa and 3180 from a 150 swift scirroco isn't too bad at all. I'm good on everything up to elk with that combo.
I haven't played with a loaded round in a while but I think that I was loading them to like 3.57. My rifle Is throated for a 175 partition to 3.565 if I recall. I'm still off the lands with the 150s but that's where I found the accuracy.
What are the options for 7 Mashburn dies? Is RCBS the only game in town and what do they get for a set? I missed a set on ebay that went for $33 because I wasn't there to bid :-(.
Does anyone rent this reamer and if not, is there a smith with one that would long chamber a barrel that I would finish? I'd prefer to do everything myself but the parts for this caliber are not generally available. Buying a new one is an option as well.
Redding had 7mm MSM dies...the S bushing dies...sitting on the shelf when I call them. It took several months to get them because Redding was so far behind in there shipping schedule. Not sure what its like now. The 7mm MSM reamer my smith has is one of his very first.From 20 some years ago.Think it was one of the very first rifles he ever built.
79: I'm sure you know all this,but barrels vary all over the map.
Some are tight, some are loose,some are rough and some are smooth. They have different numbers of lands,different throat lengths,different materials. Even how the lands are configured can affect how the bullet engages the lands and affect velocity.
All these variables can conspire together to increase or decrease resistance that the bullet encounters in traveling down the bore. Mix in different powder lots, bearing surface of different bullets,materials used,etc and it's no small wonder we see differences in the velocity from the same cartridge and bullet, and same load,from one rifle to another.And why we can even run into the pressure walls without getting the velocity we expect of a cartridge.
If we hand load enough, we have all bumped into this stuff at one time or another.
The one variable that seems to overcome all the others IMHO is case capacity,and even then we get into issues of pressures that we mostly all just take educated guesses at reading. But the point is that even though we don't alway get everything we want from a cartridge, we will generally get more than with any case that's smaller and holds less powder.
One chap (buddy) I know who had a Mashburn said that his 168 gr Barnes did not get the 3200 fps others seemed to be getting with 160 gr bullets.Velocities were barely over 3100 fps. I speculated that was because it only weighed 7 gr less than a 175 gr Partition,and maybe had even more bearing surface.
I never worked with the Barnes in the Mashburn but for yuks sometime, measure a 160 Partition.....it ain't .284.(or at least it was not the last time I measured one)...Hint.
That's pretty good stuff and your right, 3180 with that Swift is really a killer load. I actually like the expanded Swifts a little more than the ABs but both are really capable bullets.
I've tried 33 with the 175's and I'm still not sold they are gaining me anything over a load of H1000 running 50fps slower. My only need right now is getting a single jug of H1000 so I'm working with the same lot of powder. When I started with the MSM I had to buy 1lb'ers from where I could get them so a great load out of one jug turned mediocre from the next.
I've got another buddy that picked up a Simillion rechambered M70 off of here. He has yet to shoot it, but plans on running 7828 which seems like it should be just as good as H1000 or maybe better. I had plans of trying a bunch of stuff with mine but once I ran H1000 I sorta lost interest since it worked so well.
Chanlynn barrel is 26 inches and has a 1-10 twist.
The load is a 168g Berger classic hunting bullet with a Norma case and a Tula mag primer.Powder is H1000.
Measured 10 feel from the end of the barrel with my Oehler model 33 with a 10 foot spacing.4 shot groups except where noted..No errors on the chrono at all this session..
The 77.5g load has one case of the 3 fired,that has a very, very faint hint,of an ejector mark.Hard to actually tell The other two look fine.I knocked the primers out of all 3 and reprimed them.The one with the ej mark was just a little bit less effort to seat a primer with a RCBS hand priming tool.Than the other two.All 3 function through the action like butter with no tightness. Im thinking a person could actually run the 77.5g load but just looking....im afraid they would open the primer pockets over time. Ashame as the 77.5g load shot the second best accuracy at 400 yards.
The 73.5g load at 400 and the 73g load at 100 were the best for accuracy.
The 73.5g load shot an honest 3 inch 4 shot group at 400 yards. Say 3032 fps with a SD of 6.
The hotter loads were all running MOA or a bit more at 400. Conditions were kinda suckie.Wind was up pretty good.Still shot great..
I couldn't get within 3 grains of loads with the 160 grainers that other guys were running. It's okay though half moa and 3180 from a 150 swift scirroco isn't too bad at all. I'm good on everything up to elk with that combo.
What powder charge with those 150s? I'm using the same bullet in my 7 WSM and am getting 3100+.
bearstalker the people I know who are using 150's in the Mashburn are generally getting 3250 fps,or a bit more(not quite 3300) or about 100 fps more than 79 is getting with his rifle.
I got that velocity with 150's in the 7mm Dakota and the cartridges are very similar in velocity.
What mine will do with 150's I can't say as I have never fed it anything lighter than 160, unless I was fire forming.
Im thinking a person could actually run the 77.5g load but just looking....im afraid they would open the primer pockets over time.
You could load one case 10x in a row and fire it off, you'll soon see if/when the primer pockets will open. If you get to 10x and it is still holding primers satisfactorily, I would consider that load in that brass safe to go.
If I see a hint of an ejector mark. Im done. If its as hot as I think it is, you would not get to 10 reloads. And I do, do that ...ie firing the same case over and over again, to check the primer pocket.
Well I've got a 7 Mashburn FL die now and it looks like I'll be able to use my Hornady seater so once I get a reamer, I'll be in the game. I sized one piece of once fired Hornady 300mag brass and had significant puckering and cracks in the shoulder. I didn't anneal and will try that, but it looks like I might want to make up a intermediate form die. Does anyone have any pics of the brass as they come out of the form die(s)? I'd like to get an idea of how the shape progresses.
gzig: Don't use once fired cases to form your Mashburn brass.Start with new brass.
On the left is a new 300 WM case that has been passed through a Form/Trim die before being fire formed. A Pass through a FL Mashburn die should result in the same thing and no case wrinkles/buckling.
The next two cases are live fired 7mm Mashburn Super,fully formed. There is not much progression, other than a bit less taper for the Mashburn case.
Thanks for the pic Bob. I don't have any virgin brass at the moment but I did anneal a couple R-P cases and they came out OK. I'll get some new brass to start with when the time comes. Do you or any others have a favorite brand? Any that form better or are more uniform than the others?
Tried to run a new piece of brass through my FL dies and it didn't quite form it enough to get it to chamber. Guess Im going to have to invest in a forming die since the 100 pieces I formed with Dobers dies have just over 700 rounds on them so they are almost on their last leg.
Set it up to contact the top of the shell holder with the ram fully up. Then, turn the die down another 1/2 turn (maybe a bit more). Run the case in and until you feel contact and then lean on the handle and you will feel it "bump" down further.
They should chamber fine.
It had been a couple of years recently since I had to make any new brass, and I forgot to do this myself. Got to the range with a bunch of COW loads and nothing chambered.
I knew right away what I had done, so took them home and cammed them all over. They now fit fine.
I tried that Bob but it still wasn't quite enough. I may have to play with it some more. I still may end up buying the die anyways. Wife has basically taken my mashburn now anyways so I might be building myself another one this spring
Yep Dober loaned me his dies until mine came in and reamer when I first build it. Going to order my own reamer soon as I don't know if I will ever be without a mashburn
Tried to run a new piece of brass through my FL dies and it didn't quite form it enough to get it to chamber. Guess Im going to have to invest in a forming die since the 100 pieces I formed with Dobers dies have just over 700 rounds on them so they are almost on their last leg.
laker, One way to over come this without the buying a die is to take a shell holder and have your smith take .005 off the top. This will allow you to "goose" the case up into the die just enough to get the case to "fit".After the case have been fired once.you can get back to a normal shell holder.. Much cheeper than a new die. Im thinking Redding has adjusted shell holders....
That's how I feel too. I've built and bought a few other guns but they always seem to stay in the safe and the mashburn goes out so most of those have went down the road. Figured I'd build her one to simplify my reloading bench too
I use the RCBS FL resizer that I use to size Hornady 300 Win brass. I have my FL die set up to bump the shoulder .002" on the fired MSM. It makes slightly tight chambering on the reformed Hornady 300 Win brass but they pop easily out of the chamber.
I am with you guys though. I really enjoy the Mashburn though. Having a reamer is a great idea.
Bob helped me out with mine and I couldn't be happier. Been easy to load for and it works real well for me in the hunting fields.
Yep Dober loaned me his dies until mine came in and reamer when I first build it. Going to order my own reamer soon as I don't know if I will ever be without a mashburn
Laker, Who are you going with on the reamer?
I'm going to order one pretty soon. Curious how a "standard" throat, if there is such a thing, works with the 175/180 grain class of bullets for seating length. I can see myself using these more than the 195's. Or is everyone speccing the freebore by sending a loaded case? Reading everything I can find on it but it don't hurt to revisit the subject if it's been discussed elsewhere.
If your going to have a reamer made. I would pick the bullet you want to use. Or bullets you want to use, and come up with a mag length that will fit. Send dummy rounds to reamer maker. Its the only way to "know"
On last barrel I had chambered with my reamer, the smith cut the throat sepretaley at about COL 3.5 to allow for errosion and used a 1.5 deg. angle rather the more common 3 deg. for the funnel into the leade.
Yep Dober loaned me his dies until mine came in and reamer when I first build it. Going to order my own reamer soon as I don't know if I will ever be without a mashburn
Well I tried again with my FL die to form brass. I guess my first try I didn't put out enough. Had to really get after it but I got it to work. Puts a little donut on the shoulder but it chambers so it will iron out when I fireform. Now I might just pick up a stock 7mm Remington mag and ream the barrel out for the wife's mashburn
On last barrel I had chambered with my reamer, the smith cut the throat sepretaley at about COL 3.5 to allow for errosion and used a 1.5 deg. angle rather the more common 3 deg. for the funnel into the leade.
Thats one way to do it. I always have the smith use the 1 inch that they typically cut off the end of a barrel to make a barrel stub. And I always like to have my neck and free bore on the reamer itself. The stub can be used as a case gage to check how much your sizing the cases with your full length die. And the freebore on the reamer will alow you to come up with a seating depth,usuing the stub, without ever sticking a shell in the gun.
WCH: No just a single buck so far. I have been west three times since I built it,took my 270's the times out near the Bow, and have not had an elk license since Elk Mountain,the fall before I built it and used my 7 Rem Mag up there.
I always said I built that rifle too late in life as I have not hunted quite as actively as years past.A consequence of age and too many rifles.
Other hunts I have taken it on, I just have not bumped into anything to shoot.
I may put in for the Bow this year and if I draw it will come with me. Maybe I should book an elk hunt!
Bob, have you had the chance to use that big 7 on any game?
Not Bob but I can post some pictures of mashburned game
160 grain accubond
150 grain ballistic tip 150 grain ballistic tip 150 grain ballistic tip. About 20 other coyotes I don't have pictures of that have met their maker from the mashburn 150 grain ballistic tip. This is why I'm having to build another one because the wife has grown quite fond of it. Breaks my heart to have to build another one . One antelope doe and I think 7 other mule deer does and whitetail does have been taken with it too.
Bob and Laker, thanks for the answers. Some very nice game there Laker. Thanks for sharing. Never built a Mashburn. I am kind of like Bob too old and too many rifle already.. Like my custom barreled 7 mm Wea. But I like my old .300 more. No surprise to Bob.
Bob not sure what you are after for elk, but my pal and I had a fun hunt for cow elk last Jan.
Reamer showed up today. Now if I could just decide between a Lilja #2 or a brux #3 fluted. I've got a lead on both of those so those are what I'm deciding between. May put an add in the classifieds to see if someone wants to get rid of a #2 or #3 barrel
Reamer showed up today. Now if I could just decide between a Lilja #2 or a brux #3 fluted. I've got a lead on both of those so those are what I'm deciding between. May put an add in the classifieds to see if someone wants to get rid of a #2 or #3 barrel
I went with Lilja if that helps. Mr. Olson prefers to work with them as they are right down the road from him.
Reamer showed up today. Now if I could just decide between a Lilja #2 or a brux #3 fluted. I've got a lead on both of those so those are what I'm deciding between. May put an add in the classifieds to see if someone wants to get rid of a #2 or #3 barrel
Looks cool! I like my Mashburn a lot. Not sure which bullet I'll run in mine this year but I know it'll go hunting.
hey laker. how long is the barrel on your rig. What velocity are you getting from it?
My barrel is 25". The 150 grain load I'm using is running 3250fps but I can go faster she just shot better at 3250. The 160 grain load I have is 3200 fps
hey laker. how long is the barrel on your rig. What velocity are you getting from it?
My barrel is 25". The 150 grain load I'm using is running 3250fps but I can go faster she just shot better at 3250. The 160 grain load I have is 3200 fps
I'd call Hart if ordering a custom barrel. Just do happens the last four rifles I've had built were all equipped with Hart Barrels. Customer service is excellent, and their barrels are super accurate and easy to clean.
Not much to add regarding the MSM. Just an observation from using many 7's the front one is a 28 Noz, with a 25" proof barrel, witch best's the one behind it, a 7wby with a 24"bart' by 100fps, the wby best's the last one, a 7 rem with a 26" krieger by 50fps. (all with 195's).
with barrel length in consideration, they all do the same damn thing (the rem is long throat)..the MSM would fall between the 28 and 7wby, witch would equate to something like 1/4-1/2 moa difference between the whole lot of them at any given range.
the mag 7's are pretty alike, not to piss on the MSM thread, its a great cart.. just an observation. I like them all! I will own a MSM someday, pry when the rem needs a tube
Here's the wife's mashburn (still waiting on trigger guard). It's actually my old one that she took over just with new stock. Figured she could have the hand me down mashburn and I'll take the new one . Now I'll probably work up a load with 140 grain accubonds, 150 grain partition, or just stick with the 150 grain nosler ballistic tip load I already have for it but what fun would that be.
Here's the wife's mashburn (still waiting on trigger guard). It's actually my old one that she took over just with new stock. Figured she could have the hand me down mashburn and I'll take the new one . Now I'll probably work up a load with 140 grain accubonds, 150 grain partition, or just stick with the 150 grain nosler ballistic tip load I already have for it but what fun would that be.
Sweet! Try some 195's. One of the easiest bullets i've ever worked with, they want to fly, just control run out and get out of the way!
8 twist 7rem, IMR 7977, 4 shot 195's
28 Noz 9 twist, 4 shot, Retumbo..slight depth tweek in order on this one.
Bob I haven't bought a scope in the last ten years that wasn't either a fixed 4 or 6. But Scotty's VX-6 looks pretty good, and Matt had a Swarovski last fall that had some great glass. I've also looked through some Nightforce scopes and they look high quality.
I don't know about dropping $1500 on a scope when the 6x36 will get everything done for $450 (with Aluminas), but I might be able to talk myself into $1K.
If it matters I'm not much of a turret turner. I tried M1s once and they didn't grow on me. I can see the practical use of turrets for training, but I have not missed an opportunity at killing an animal that was far enough away to need turrets, but still close enough to have a reasonable chance. I did once encounter a bull at 750 yards, but he was moving, so turrets wouldn't have mattered. His antlers looked good in the sun though! I'm sure had he been within 400 yards I would have sent one, hoping like hell he'd stop for a second.
Joel then you sound like a candidate for a 6x36 with the dots. Don't spend the cash if you don't need to.
From a 2.5" high zero at 100 yards with that Amax, that reticle will get you to 600....no turrets if you don't want to use them. A 160 AB only slightly less.
That's pretty good stuff and your right, 3180 with that Swift is really a killer load. I actually like the expanded Swifts a little more than the ABs but both are really capable bullets.
I've tried 33 with the 175's and I'm still not sold they are gaining me anything over a load of H1000 running 50fps slower. My only need right now is getting a single jug of H1000 so I'm working with the same lot of powder. When I started with the MSM I had to buy 1lb'ers from where I could get them so a great load out of one jug turned mediocre from the next.
I've got another buddy that picked up a Simillion rechambered M70 off of here. He has yet to shoot it, but plans on running 7828 which seems like it should be just as good as H1000 or maybe better. I had plans of trying a bunch of stuff with mine but once I ran H1000 I sorta lost interest since it worked so well.
I wonder who that guy is. Sure is a nice rifle. Nice light and handy. Got some Fireforming loads down her while the wind was blowing the other day and I'm pretty happy with it so far 65 of 4350 and 140 BT shot a half inch group in the only calm I saw and accounted for a jackrabbit. Really excited to have a chance to start loading it. I got a pile of 160 AB PT PTG and 175 PT to run. Gonna beat the hell outta my 280 AI for packing 11lbs naked this one hits 8lbs 2oz field ready.
. Gonna beat the hell outta my 280 AI for packing 11lbs naked this one hits 8lbs 2oz field ready.
nv: How did you end up with an 11 pound 280AI? What is that for?
Your lightweight Mashburn is a "280AI with FF loads,and with full house loads will run rings and circles around the 280AI,so sounds like you are set.
We found 7828 worked well enough but did not show any better, if as well, as H1000,RL25,and retumbo. Keep in mind most all this work was with 160-175 gr bullets.
I have seen no reason to move from H1000, although it does vary among lots (so does Retumbo),and recent lots seem slower. I'd buy an 8 pounder.
Well I got 10lbs of 7828 so it will get the call might try RL26 as well it's what I have on hand. Nowhere local has H1000 so I'd have to order a keg plus some other stuff to make it worth while. It's got a VX3 on it right now but I picked up a VX6 and VXR for cheap so that's what will go on it.
I'm gonna run 160-175 I got a slew of other 7's for the lighter stuff. I really like it so far FF's are cream puffs. Hopefully will be able to do some testing this week.
That 280AI will now be used to hold down the safe. I really liked it but with the ideas I had in mind for it this is what I should have down in the first place. Young and dumb!
Well I got 10lbs of 7828 so it will get the call might try RL26 as well it's what I have on hand. Nowhere local has H1000 so I'd have to order a keg plus some other stuff to make it worth while. It's got a VX3 on it right now but I picked up a VX6 and VXR for cheap so that's what will go on it.
I'm gonna run 160-175 I got a slew of other 7's for the lighter stuff. I really like it so far FF's are cream puffs. Hopefully will be able to do some testing this week.
That 280AI will now be used to hold down the safe. I really liked it but with the ideas I had in mind for it this is what I should have down in the first place. Young and dumb!
Not young and dumb. You can only expect so much from a 30/06 case, no matter how you stretch it.
Even on slow days and with slow lots of powders the Mashburn gives as much velocity as a 7 RM loaded to the gills, so don't worry.
7828 shot well,in mine, with the 150g ballistic tip. But I thought it was a bit sootie/dirty. Not really an issue as I wasnt shooting a match with it. H1000 seems cleaner burning to me. My H1000 seems a bit slow from what ive read here. But accuracy wise. Ill take it..
In Quickload, if I optimize best powder for that cartridge at 65 kpsi with the same 162 gr bullet for velocity with (16) different 7mm cartridges, the point of diminishing returns is around the 280AI and 7mmRemMag point.
After that, it is a lot more powder for small velocity increase.
Swell. Point being "what"? You said noting I didn't know years ago.
So what if they are more "efficient"? They are also "slower".
You can read theory until the cows come home. If you want to move a 175-180 gr 7mm bullet at 3100+ fps from a 24-26" barrel (what I wanted) you can toss silly formulas out the window. You need capacity.The 280AI and 7 Rem Mag are also rans.
Ask Rick Camuglia and Dave 7mm what they think about the Mashburn when it comes to moving heavy 7mm bullets.
If I want to throttle back, I get 280AI velocities from my FF loads before I reach full Mashburn potential. Good for playtime and making cases.
I have had a slew of 7 Rem Mags and have shot out more barrels chambered for it than many have owned.
The 280AI interests me about as much as nothing and is a solid step in reverse. If i want one i can build/buy one tomorrow. I don't.
Reading QL is fine for home entertainment. Try chambering barrels and shooting.
WCH; I never kept count on each barrel. I am not that organized.
If I were to give best estimate I'd say maybe a couple thousand rounds. But that's a guess.
m
I've got a little over 700 rounds through one of my mashburns. Curious barrel life of a mashburn. Might have to text Dober and see how many rounds his have went before going belly up
Swell. Point being "what"? You said noting I didn't know years ago.
So what if they are more "efficient"? They are also "slower".
You can read theory until the cows come home. If you want to move a 175-180 gr 7mm bullet at 3100+ fps from a 24-26" barrel (what I wanted) you can toss silly formulas out the window. You need capacity.The 280AI and 7 Rem Mag are also rans.
Ask Rick Camuglia and Dave 7mm what they think about the Mashburn when it comes to moving heavy 7mm bullets.
If I want to throttle back, I get 280AI velocities from my FF loads before I reach full Mashburn potential. Good for playtime and making cases.
I have had a slew of 7 Rem Mags and have shot out more barrels chambered for it than many have owned.
The 280AI interests me about as much as nothing and is a solid step in reverse. If i want one i can build/buy one tomorrow. I don't.
Reading QL is fine for home entertainment. Try chambering barrels and shooting.
Sorry if my optimization algorithm offended you. I own two 7mmREMMAG reamers and have chambered a number of rifles with them; Rem700, 98 Mauser, and Mosin Nagant. Factory rifles 7mmRM; Ruger #1, Browning 1885, Sav 110, Rem700. I have a bunch of 7x57 and 7mmBR gear too. I am in the process of of chambering more 7mmRemMag rifles right now. I build a lot of rifles with a lot of different cartridges, but I kill the most animals with 7mmRM. I consider it to be the most power, range, and accuracy for the average shooter in a 10 pound package.
Clark I'm not offended by optimization theories. The problem with them is that they say..."Well that case goes slower but it's more efficient per grain of powder."
Well so what? If you want velocity (performance) you may have to leave some "efficiency" on the table.
I simply don't agree that nirvana in a 7mm magnum case lies with the 7 Rem Mag. It starts to stall with 7mm bullets from 160 gr and up,where the real advantage to 7mm bore size exists.
I've found the 7mm Dakota/Mashburn cases to be more "optimum" with those bullet weights, without reaching for crazy capacity,because we still have to make rifles we can carry, and shoot accurately with barrels of moderate weight and length.
All the Mashburn does, is provide a longer neck and increased capacity for more velocity without going overboard.
Since you have the tooling,you could grab a Mashburn reamer and try for yourself. That's always more interesting .
One thing that frequently makes me chuckle are the calls I get from new Mashburn users who say...."I just dumped 75-78 gr of (whatever) H1000 in there and there's still lots of room!. This thing holds a lot of powder!"
I tell them that's the reason it will make a 160 gr bullet go 3250 fps., or a 175 gr almost 3100....if you want.
It's hard to get all excited about 7 Rem Mags after that....to me anyway. I have to ask,with todays better powders and super LR bullets 160 gr and up, what is "optimum"?
In a 10lb package? Whew, there is no way I'm packing a rig that heavy for general hunting. If it's a got a 45cal hole in the barrel I might consider it, but those are special purpose rifles. The Mashburn is the best overall in a magnum case, just as Bob and others have said, if the user wants to drive heavy bullets fast.
Not trying to defend Bob (who needs no defense), but as an unabashed 30-06 admirer I will say I have some buddies who convinced me to try the 7 MSM. I thought about it for a good while, because I have now two exceptional 30-06 rifles (that would have served me well for years to come), and the reason I was convinced to try the MSM boils down to a difference of 100 yards.
I use a Leupold 6x42 LRD on my primary 30-06. I sight the rifle in with either 165 or 180 grain bullets, moving at 2900 and 2800 fps respectively. I choose a sight-in distance such that the bullet doesn't more than 3 inches high at MPBR. For my 30-06 that means about 215 yards, and the bullet is 3 inches low about 275 or 280 yards away. Then the first dot of the LRD is about 300 yards, the second about 400 yards.
I can sight in the 7 MSM, with a 160 AB moving about 3200 fps, with the same 3-inch trajectory consideration, at 250 yards. I need to move to the first dot around 375 yards, and the second dot gets me to almost 500 yards. Some of this advantage is the starting velocity 300-400 fps faster than the 30-06. Some is the BC of the 7 mm bullets available.
The 280 AI and 7 Rem Mag use the same bullets as the MSM, but lack the extra velocity. The bottom line is I don't think they provide enough advantage to dedicate another keg of powder (because a new chambering for me means another keg of powder--I don't like to [bleep] around with too many powders) to my stores. But a 100 yard advantage out west hunting elk--that's a reason to give the MSM a spot in the gun safe. And my bigger than life buddy tells me the recoil won't be unmanageable...
...and I became introduced to a rifle that just happened to be chambered already in a custom quality Remington 700 package, complete with already chambered spare Lilja barrel.
I've decided that life would be much more complete with a fast 7mm and have it down to 3 options after reading too many threads on here. Basically looking for a 160 at around 3100 but wouldn't be disappointed if velocity was slightly less. Input on which way you would go is greatly appreciated...
1)long throating a 7mm rem mag. Figure that if I keep over all length around 3.3 I should see some of the benefits of the weatherby with cheaper brass costs and be able to shoot factory ammo in a pinch.
2) 7mm weatherby, only down side is higher cost of brass and scarce factory ammo around here.
3) the mashburn. If i use a form/trim die is fire forming still necessary for full power loads? Also, I would like to have headstamped brass when possible if i travel to hunt. I've saw where quality cart. sells it but have heard differing things about the quality.
Make the MSM. I use the COW method to final form brass; it doesn't waste bullets and expensive powder. Any pistol or shotgun powder will work. Bob has Quality brass and 40 should last quite a few hunts. For anything in the US, reformed .300 Win. is cheap and in endless supply.
As a disclaimer, I have 2 MSM's and one is a rechambered 7 Rem.
I've not fire formed before or had a wildcat before. Do you just run the 300 win brass through the full length die and load up a light charge with the cream of wheat and then bang away?
I'm leaning towards the rechambered 7 rem as they're pretty easy to find cheap around here
Kelly honestly you could go with any of the three. Long throat a 7 RM I think you'll get there. Plus /minus 3100 with a 160 should not be hard with todays powders.
The 7mm Weatherby is a slam dunk (I guess, never owned one). But reliable people on here get over 3100 routinely.
I'm happy with the Mashburn (which started out as something of an experiment) and like it a lot but the wildcat status and forming cases is a turn off for lots of people. Others are not bothered by it at all.
I bought the Quality Cartridge stuff but people on here gave me subtle hints about how good it was. I have not tried it so can't comment.
If head stamped brass is a concern, go Weatherby,7 RM etc etc.. But I know friends of mine hunting with Mashburns have taken rifles and cartridges into Mexico and Canada.I have not flown with mine yet, but am not really worried. Pay your money and pick your poison.
You could make life real simple and just get a 28 Nosler!
To COW form; form, prime, load with 20 +/- gr of just about any fast powder, toilet paper wad, COW, plug of canning wax, shoot.
Bob has a hunting fire form load with 140 gr that is accurate if you use bullets that light for deer hunting. One thing you will need to do is anneal the necks on the cases after about 4 loadings. If you will do this, it will last almost forever. I use 7 Roy load data. It has a pretty good margin of safety since the MSM has more case capacity.
I much prefer MSM to any of the others and I don't have a 28 Nosler.
Doc is less reluctant to recommend the wildcat than I am. ...but we both like it best.
It isn't hard to do. below are COW formed Mahburn cases, recently made.
Recipe for COW: CCI large pistol primer.13 gr Alliant Bullseye. Fill to base of neck with RCBS dried corn husk tumbling media. Top off with a wad of tissue.
OR
Form and charge with 65-IMR4350-139 Hornady (or some other favorite 140 gr bullet works for other folks). This is a below max pressure load that is no toy and will show 3150 fps or so. You could easily hunt with this stuff.
Just for information, I make all my 7 mm Wea. Brass out of 7 mm Rem cases. One pass through the Wea die and my brass is formed, and a bit short so no trimming needed for a while. My Wea is on 700 action so I am able to seat a 160 flush with the bottom of the neck. Last time I checked I was getting about 3250fps with the 160's. Solves the issue of getting Wea brass.
Still the Mashburn has much to recommend it. Probably if I were going to make a new big 7 to day, I would give the Mashburn a close look. Have considered rechambering my old 7 mm Rem to the Mashburn case. It is 1200 plus rounds old, that might give me a "new", rifle without a rebarrel job. The only thing is this old 7 was my late wife,s favorite big game rifle,and I am pretty much a .30 caliber guy.
7mm mashburn is one of the easiest wildcats I've ever messed with. I've been running 300 win mag into my mashburn FL die and been working fine vs using the form and trim die. I say go for it
7mm mashburn is one of the easiest wildcats I've ever messed with. I've been running 300 win mag into my mashburn FL die and been working fine vs using the form and trim die. I say go for it
Same here, I borrowed my first set of 7mm MSM dies from another fellow MSM shooter while I was waiting on my dies from Midway. Once I got the new ones, I simply forwarded them back to my buddy and kept his old ones since I have them all set up for my rifle.
I was a little hesitant to do all that fireforming but honestly, I can't hurt the first 50 cases I formed a year ago. I anneal them regularly and they just last. I have ran 65 grains of IMR4350 with 140 Accubonds, 139 Hornady SPBT's, 140 BT's, 145 Speers, 140 Sierra's and probably some others I have forgotten. All of them net around 3150-3200. This last time I used some IMR4451 to do my forming since it was supposed to be a little cleaner, but it was only around 2980 or so.. No big deal either way, the cases come out perfect.
I will say when I started with MSM, Bob and another said get some H1000. I did and followed their lead. Took all of about 24 rounds to get me a load with the 160 AB and the speed they said (3200). My only problem was all I could get were 1 pounders back then. A couple of them were from the same lot, but I ended up with 75.5 with the 160 AB's (3200) and 73 for the 175's (3050).. Well, I was finally able to get a fresh 8 pounder of H1000.. Quite alot slower than my older 1 pound containers as 73 grains with a 175 PT only netted me about 2890.. Not a big deal, I'll just keep adding coal to get it up to 3050 again and I'll have that load for a long time I bet.
I like the cartridge so much because of the ability to run a lighter rifle and maintain some excellent reach. Blasted a poor cow this past fast in Wyoming and it just stunned her at 250 yards with the 160 AB. Blew on through and she lifted her head up once and was done.. Nothing special and I am sure elk hunters have seen it a million times, but is nice to have a 0-500 yard rifle without having to think of much of anything.
Mines just an old beat up 70 XTR that a great friend let me borrow a reamer for. That rifle has turned out some EXCELLENT groups for me on the factory barrel. I have liked the cartridge so much, I am pretty sure when I can put aside some loot, I'd like to have a nicer one made up. Till then, I'll keep slumming this old, ugly Model 70..
Another nice part, that I think Doc Bill mentioned was being able to use 7mm Wby data to work up with. I recently tried that with some 150 ETip's. It works, you don't have to stone wall the MSM to get Weatherby speeds at all.
Just my take on it so far, but I hardly ever go to the range without it honestly. I have a harder time picking a bullet I wanna run out of it than anything else..
nv:With the old stand by single base propellants like 7828,H4831,even H 1000, you are going to see something like 3050-3075 from a 175 gr bullet. Powders like RETUMBO,and RL25 will show a bit more.
With those two powders a 160 will show up to 3250 with no concerns in any 24" barrel I have seen used
I don't like to see any more than a hair under 3100 with the 175; nor more than 3250 with the 160 from the case and 24" barrel, regardless of powder, although longer barrels will show more speed.
I think those parameters were designed into the cartridge 50+ years ago and create a very potent open country BG cartridge.
Perfect. I'll have to try it. Was that Max in your rifle? And yours is a 24" tube correct?
Yes a 24" tube. I wasn't flattening primers or anything but I figured 3200 with a 160 was enough. Never pushed it any harder
Just wondering if you pushed it up to see pressure so I had an idea. Start at 68 and should be good. How was the accuracy?
Have you tried 168 ABLR or 175 PT?
You should be good to start at 68 grains. I only ran 160 grain accubonds and 150 grain ballistic tips. Both very accurate. I just stuck with the 150 grain ballistic Tips because I was shooting to much and the accubonds got to expensive to bang steal with
nv:With the old stand by single base propellants like 7828,H4831,even H 1000, you are going to see something like 3050-3075 from a 175 gr bullet. Powders like RETUMBO,and RL25 will show a bit more.
With those two powders a 160 will show up to 3250 with no concerns in any 24" barrel I have seen used
I don't like to see any more than a hair under 3100 with the 175; nor more than 3250 with the 160 from the case and 24" barrel, regardless of powder, although longer barrels will show more speed.
I think those parameters were designed into the cartridge 50+ years ago and create a very potent open country BG cartridge.
3050 is what I'm hoping for just was trying to see if I need to get a jug of H1000 or if anyone had any data on 7828. 3200 with a 160 is plenty just trying to get some ballpark numbers as a start. Got some cases ready to load.
I know yourself and others have said 7Bee data is safe but just trying to do a little extra due diligence.
Just offering observations based on what we have seen first hand from the cartridge with different powders.
It's still a wildcat,so we are on our own.......Knowing I could push it faster, I have always tried to stay on the conservative side and have still been impressed with how "easy" and tractable it is to load.
Be careful with the 7mm Weatherby data....I know first hand the RETUMBO data with 160's is very hot if you approach MAX in the Nosler manual. The 7mm Weatherby seems to be loaded pretty hot. I would work up to any 7mm Weatherby data in the Mashburn from below, to be safe.
Well hello Bob. Been a while sense I grazed the pages of the campfire and first thing I see is Mashburn. I need to break mine out of the safe and burn some powder.
Just offering observations based on what we have seen first hand from the cartridge with different powders.
It's still a wildcat,so we are on our own.......Knowing I could push it faster, I have always tried to stay on the conservative side and have still been impressed with how "easy" and tractable it is to load.
Be careful with the 7mm Weatherby data....I know first hand the RETUMBO data with 160's is very hot if you approach MAX in the Nosler manual. The 7mm Weatherby seems to be loaded pretty hot. I would work up to any 7mm Weatherby data in the Mashburn from below, to be safe.
Agree with this. I know when most folks ask me about data for the MSM, I usually direct them at published WBY data as a starter. Bob nailed it by saying start at the bottom. You'll see straight away with your chrono where you stand. It's about the closest thing we have for published data if you want a baseline.
Jake, I'm looking forward to your work with 7828 and the 150-175 class Bullets. Seems like any of them will really do excellent in the MSM.
Just offering observations based on what we have seen first hand from the cartridge with different powders.
It's still a wildcat,so we are on our own.......Knowing I could push it faster, I have always tried to stay on the conservative side and have still been impressed with how "easy" and tractable it is to load.
Be careful with the 7mm Weatherby data....I know first hand the RETUMBO data with 160's is very hot if you approach MAX in the Nosler manual. The 7mm Weatherby seems to be loaded pretty hot. I would work up to any 7mm Weatherby data in the Mashburn from below, to be safe.
Agree with this. I know when most folks ask me about data for the MSM, I usually direct them at published WBY data as a starter. Bob nailed it by saying start at the bottom. You'll see straight away with your chrono where you stand. It's about the closest thing we have for published data if you want a baseline.
Jake, I'm looking forward to your work with 7828 and the 150-175 class Bullets. Seems like any of them will really do excellent in the MSM.
Yeah. This ain't my first rodeo with a wildcat. Got a 338-06AI 6-284 then a bunch of old cartridges that in a good modern action can be pushed a bit harder than the 45-55k they were approved at back in the day and that factory rounds are loaded at. Seems like you guys have got it figured out so it will help me get there a bit quicker. The 338-06AI was an adventure since there isn't as much info out there on it. The 6-284 was as well. I did pop a primer on the 6-284 first time seeing that don't want to repeat it for dang sure. Learned a lot from those two. With as much info as there is here on the Mizzum I hope to not repeat any of the lessons I previously learned.
Hopefully I can post some results Thursday or Friday.
For anyone looking to build a Mashburn, I have a reamer that could be loaned out. If I like you and approve of the smith that will be using it. I recommend Redneck.
Hey beretzs, I've seen old ugly. The only way that would hurt my eyes is if I got to close to the scope. Pain would go away when I seen the group though
Hey beretzs, I've seen old ugly. The only way that would hurt my eyes is if I got to close to the scope. Pain would go away when I seen the group though
Good point. It is hard for me to abandon it just yet, it is still shooting well..
Today got some shooting in with it. Running 175PT with 7828SSC. 66-2958 67-2995 68-3049 69-3111 too hot. Really stunk when I loaded 69-71 and had to pull everything I loaded and start over.
Shot groups at 67 67.5 and 68
67 was a start had no clue went about 1.5" 67.5" went 1" 2-1 68 opened way up and the last in the group showed just a hair of pressure. These were all loaded @ 3.480"
Went back to the bench loaded some more 3.470" went under 3/4" and 3.460" opened up in a pattern 1 right 2 left 1 right.
Will shoot 3.470" and play down to 3.465" hopefully she'll suck them in. A 175PT @ 3020-3030 should be good elk medicine.
Sounds like you're there with 7828. I'd play with seating and shoot it to 300 yds plus next.
Thing I love about the Mashburn is that even lolly gagging with starting loads you're right there with top end 7 mag loads. No mysteries about "where'd my velocities go?" LOL
Today got some shooting in with it. Running 175PT with 7828SSC. 66-2958 67-2995 68-3049 69-3111 too hot. Really stunk when I loaded 69-71 and had to pull everything I loaded and start over.
Shot groups at 67 67.5 and 68
67 was a start had no clue went about 1.5" 67.5" went 1" 2-1 68 opened way up and the last in the group showed just a hair of pressure. These were all loaded @ 3.480"
Went back to the bench loaded some more 3.470" went under 3/4" and 3.460" opened up in a pattern 1 right 2 left 1 right.
Will shoot 3.470" and play down to 3.465" hopefully she'll suck them in. A 175PT @ 3020-3030 should be good elk medicine.
Looking good. You analyze this chit the way it needs to be done. Something a lot of guys can't do. What part of NV?
Today got some shooting in with it. Running 175PT with 7828SSC. 66-2958 67-2995 68-3049 69-3111 too hot. Really stunk when I loaded 69-71 and had to pull everything I loaded and start over.
Shot groups at 67 67.5 and 68
67 was a start had no clue went about 1.5" 67.5" went 1" 2-1 68 opened way up and the last in the group showed just a hair of pressure. These were all loaded @ 3.480"
Went back to the bench loaded some more 3.470" went under 3/4" and 3.460" opened up in a pattern 1 right 2 left 1 right.
Will shoot 3.470" and play down to 3.465" hopefully she'll suck them in. A 175PT @ 3020-3030 should be good elk medicine.
Looking good. You analyze this chit the way it needs to be done. Something a lot of guys can't do. What part of NV?
Today got some shooting in with it. Running 175PT with 7828SSC. 66-2958 67-2995 68-3049 69-3111 too hot. Really stunk when I loaded 69-71 and had to pull everything I loaded and start over.
Shot groups at 67 67.5 and 68
67 was a start had no clue went about 1.5" 67.5" went 1" 2-1 68 opened way up and the last in the group showed just a hair of pressure. These were all loaded @ 3.480"
Went back to the bench loaded some more 3.470" went under 3/4" and 3.460" opened up in a pattern 1 right 2 left 1 right.
Will shoot 3.470" and play down to 3.465" hopefully she'll suck them in. A 175PT @ 3020-3030 should be good elk medicine.
Looking good. You analyze this chit the way it needs to be done. Something a lot of guys can't do. What part of NV?
North central. Between Winnemucca and Elko
Sounds like the Battle Mountain area. I grew up in Winnemucca... A lot of jack rabbit slaying got done when I lived there... . Your 7 will work on those too... They make excellent offhand target practice...
I made another 100 pieces of Mashburn brass yesterday. I thought I'd post the process for those who've never done any case forming and are a bit intimidated. It's really straightforward.
The series of pictures with the COW (cream of wheat) loading are actually 7mm RUM brass that were necked down from .300 RUM, but the process is the same.
First, run .300 Winchester Magnum brass through the 7mm Mashburn Super sizing die. I found that the only real part of the case that gets any sizing is the shoulder and neck so I simply get lube on my thumb and forefinger and coat the neck and shoulder slightly before running it though the die. Lube the inside case neck too...
These are actually 7 MSM brass and their parent, the .300 WM
The little ring you see toward the neck/shoulder junction is where I stopped neck turning when the brass were originally .300 WM. After forming, I re-turned the brass to the new neck/shoulder junction and even into the shoulder a tad to eliminate any donut situation. This is the final product:
After sizing, I prime, load 20 grains of fast-burning powder (not critical. Unique, Red Dot, etc..) and fill with COW (I use coarse Polenta ) to the shoulder area...
When I did these, I filled them too full into the neck. Just shake some out to allow for the next step...
Melt some paraffin wax in a double boiler and use some sort of eye dropper to dispense it into the case to the top of the case mouth...
At this point when the wax has cured, go out and chamber shells and pull the trigger to form. The batch I just got done forming was pretty much fully formed in length anyway.
Nice Rick I like the other method using lead out the barrel myself. Good post though very thorough.
Shot a few more of the 175 7828 loads. I backed down to 66.5 still at 1.25" played with seating depth either the nut behind the trigger was beat up or I'm a little off. 67.5 I couldn't get to repeat and I thought it may still be on the warmish side since I decided to use 3 cases and just use them over and over and after 4 firings the pockets are a little on the squishy side.
So I'm gonna try some RL26 and some H1000 is on the way. Thinking my lot of 7828 is a little on the fast side. Ran a QL and with my velocities 69 gr should have been right at 65k I think I was pushing 68-70k with the pressure signs I got.
NV: Suspect you will find what we did with 7828, H4831 ec, that those older sing base powers were good back in the day, and still work with lighter bullets,,,,but the newer slower powders do a better job in the larger case with the bullets 160 and up. Things like R25 (have not tried 26 yet), H1000, retumbo etc. just give better results.
Noticed the same with the 7mm Dakota which is a really a belt less Mashburn for practical purposes.
Well, I've been working with the 150 Etip a little in the Mashburn. Gotta say it's coming together fairly quick.
I think maybe a little deeper and I can call that one done. On to the 175 PTs :lol:
I got a new 8lb jug of H1000 and it's quite a bit slower than my old one. I was running 73 grains to get 3050. With new jug I'm up around 75 to get a touch over 3000. I'm not going to fight for 50 FPS as long as accuracy holds up, which I think it will.
So I have a touch more work but dang if this MSM isn't EASY. Just feed it a powder that's slowish and a decent bullet. It's a pretty cool hitter. Ol Art Mashburn got this one on the money! :mrgreen:
Here's my second Mashburn I picked up from the smith tonight. Remington 700, #3 lilja cut to 25", Leupold 6x42 with m1 turret sitting in talleys, timney trigger, all sitting in a mcmillan classic edge stock. Scoped and with a Montana sling and 3 in the belly she is 8lbs on the nose. Now if the wind would quit so i could get to the range.
Laker, love that caliber.. I was a real fan of Bob Hagel.. That was his favorite big game caliber! Hope it is as lucky for you as the first.. I liked hearing about the game you and your gal took with that older rifle. Keep us posted on your success with this new one! Being old, not as old as Ingwe, but old, I can't really warm up to the plastic stock , but you are young and can enjoy that style! Very best of luck with a fine rifle!
Here's my second Mashburn I picked up from the smith tonight. Remington 700, #3 lilja cut to 25", Leupold 6x42 with m1 turret sitting in talleys, timney trigger, all sitting in a mcmillan classic edge stock. Scoped and with a Montana sling and 3 in the belly she is 8lbs on the nose. Now if the wind would quit so i could get to the range.
Laker, that thing came out really sweet... I want to know what it'll do with 180 Scenars or 195s...
70 shot the best so played with seating depth from about 3.492" down to 3.460". 70 and 60 shot the best around 3/4" with 60 being 2 same hole one about .75" out. Might have a harmonic issue with the rifle as well. When I shot the 60 group first 2 were spread then 3&4 were 2" low right and 5 going in same hole as #1. I thought initially I pulled 3 so went loaded one and 4 went same spot so went loaded another and it went into the same hole as one.
Pretty fatigued at that point had shot around 35 rounds.
70 shot the best so played with seating depth from about 3.492" down to 3.460". 70 and 60 shot the best around 3/4" with 60 being 2 same hole one about .75" out. Might have a harmonic issue with the rifle as well. When I shot the 60 group first 2 were spread then 3&4 were 2" low right and 5 going in same hole as #1. I thought initially I pulled 3 so went loaded one and 4 went same spot so went loaded another and it went into the same hole as one.
Pretty fatigued at that point had shot around 35 rounds.
That sounds about right from a 24" barrel....ditto on the 180-195's as a target velocity.
It'll vary a bit depending on barrels....like any other cartridge.
Here's my second Mashburn I picked up from the smith tonight. Remington 700, #3 lilja cut to 25", Leupold 6x42 with m1 turret sitting in talleys, timney trigger, all sitting in a mcmillan classic edge stock. Scoped and with a Montana sling and 3 in the belly she is 8lbs on the nose. Now if the wind would quit so i could get to the range.
Laker, that thing came out really sweet... I want to know what it'll do with 180 Scenars or 195s...
Tanner
Id love to play with the 180 grain scenars but I'm not sure how they'd be plowing into an elks shoulder at 50 yards. Most of the reports I've read have been longer range shots with that bullet. And where I elk hunt I could get a 20 yard shot or a 500 yard shot. Who knows maybe I'll get my elk with my bow this year and start playing with that bullet
Here's my second Mashburn I picked up from the smith tonight. Remington 700, #3 lilja cut to 25", Leupold 6x42 with m1 turret sitting in talleys, timney trigger, all sitting in a mcmillan classic edge stock. Scoped and with a Montana sling and 3 in the belly she is 8lbs on the nose. Now if the wind would quit so i could get to the range.
Laker, that thing came out really sweet... I want to know what it'll do with 180 Scenars or 195s...
Tanner
Id love to play with the 180 grain scenars but I'm not sure how they'd be plowing into an elks shoulder at 50 yards. Most of the reports I've read have been longer range shots with that bullet. And where I elk hunt I could get a 20 yard shot or a 500 yard shot. Who knows maybe I'll get my elk with my bow this year and start playing with that bullet
I personally would not be scared of that shot but I understand the reservation... Think you'd end up with an extremely dead elk very quickly...grin
A 175 NPT will EASILY handle both the 50 yard chip shot through shoulders....and the 500 yard poke.
Just saying'
So, for that matter, won't the 160 NPT.
For now I'm going to try 160 grain accubond and of course 150 grain ballistic tips. But there are nosler partitions in 160 and 175 grain seconds instock for $16.95 that I may end up ordering
Loaded up 3 fireformed loads with 150 grain ballistic tips and the rest using the cream of wheat fireforming. I my shoulder sure feels better with the cream of wheat. I'd say she is going to be a shooter.
Looks great! What is your FF load with the 150 BT?
COW loads are an easy hour at the range without all the big noise
Bob those 3 were actually already fireformed cases. I stuck 71 grains of IMR 7828 under the 150 grain ballistic tip and that's what became of it. Couldn't get a chrony reading with the morning sun but my guess would be 3150-3200. With a 6x scope I will take that. Sometime this week Im going to play with H1000 and 160 grain accubonds
Trying to hard at 100 is a lot of my problem. Rapid fire I can stack shot after shot. Same gun same load slow fire will be 1.25"-1.5". Longer range are, correct for the wind and break the trigger and they hit where they should.
It is not that uncommon for VLD bullets to shoot better at longer ranges than a short 100yds. Depends on the bullet/barrel combo, not a hard rule. Something about the long bullets needing some time/distance to "go to sleep". I've seen it working up loads for my Palma and LR Prone rifles. I have easiest access to a 200yd range and do most of my load workup there and then verify at 600 or 800. There have been several times where the statistical results at 600+ were quite a bit better than what the 200yd groups would have predicted for a given load shot at both distances on same range on same day.
It is not that uncommon for VLD bullets to shoot better at longer ranges than a short 100yds. Depends on the bullet/barrel combo, not a hard rule. Something about the long bullets needing some time/distance to "go to sleep". I've seen it working up loads for my Palma and LR Prone rifles. I have easiest access to a 200yd range and do most of my load workup there and then verify at 600 or 800. There have been several times where the statistical results at 600+ were quite a bit better than what the 200yd groups would have predicted for a given load shot at both distances on same range on same day.
People say this isn't possible but I have heard the same thing from so many match shooters that I just accept it any more...even though I'm not a match shooter.
And it seems to pop up as a subject with long heavy for caliber bullets,especially when driven from high velocity magnum cartridges.
Yep I've seen it as well with VLD's, you never know. Guy I know who shot at Perry for years said their loads were 3/4" at 100 and half minute at 1k. Great shooting.
Well I've got myself quite the dilemma. I've got a load worked up with 150 grain ballistic tips at 3300fps, a 150 grain partition at 3250fps, or a 160 grain accubond at 3200fps. Such a terrible problem I have. I'll probably run the !ballistic tips just cause I can shoot a lot more of them for cheaper and I've yet to be disappointed in them
Well I've got myself quite the dilemma. I've got a load worked up with 150 grain ballistic tips at 3300fps, a 150 grain partition at 3250fps, or a 160 grain accubond at 3200fps. Such a terrible problem I have. I'll probably run the !ballistic tips just cause I can shoot a lot more of them for cheaper and I've yet to be disappointed in them
Problems problems...Laker life is just tough like that sometimes.
John, I'd like to think so but I met Bryan several years ago at the Midwest Palma matches in Lodi when I won the Wisconsin 1000yd championship for Master class. I think this was before he finished his book and started gaining national notoriety. We shot on the same point and I got to pull and score for him. There is no doubt in my mind that Brian doesn't need my help. :-) Not only is he a very intelligent engineer, he is a fantastic shooter and wind reader. In a no-wind or constant wind situation, he would just tear up the 6" spotter disk in the X-ring at 1000yds shooting prone from a sling with iron sights. It was a great experience. He freely offered advice to other competitors and I learned a lot.
I have no way to know, but wonder if these were not loaded by Art Masburn or someone in his shop. It came with a rifle marked Mashburn Arms and the rifle appears to not have been shot much.
![[Linked Image]](http://i400.photobucket.com/albums/pp83/skane_image/Bobs_7mmMashburnSuper.jpg)
![[Linked Image]](http://i400.photobucket.com/albums/pp83/skane_image/MASH_2.jpg)
![[Linked Image]](http://i400.photobucket.com/albums/pp83/skane_image/mashburncases.jpg)
![[Linked Image]](http://imagizer.imageshack.us/v2/280x200q90/709/nhbuck2010.jpg)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/2015%20Wyoming%20Elk%20Hunt/79FC8523-7D14-4638-849F-8A6FCE6F39AF_zpsrbv4bdoy.jpg.html)
![[Linked Image]](http://i1182.photobucket.com/albums/x456/jfeiger/litz_zps9se7ue5e.jpg)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/9B651E15-9417-44FC-A586-D093632B0E61.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/6EA0EB6C-0F19-4EAD-B284-53404EDDB38A.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/Mobile%20Uploads/2016-02/683569F2-3938-4654-A930-E24FDF544B10.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/6343DAED-42C7-494B-80A4-00C2BE6048DF_zpsai1uialt.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/1CA71BC9-51DC-4954-896E-67AB6634CFA6_zpsnh3tqqx4.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/Mobile%20Uploads/2016-02/36C3AE35-A2C8-413A-A56B-395D66A59EDC.png.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/Mobile%20Uploads/2016-02/43E41BE9-D372-458E-9845-63074D8C7829.png.html)
![[Linked Image]](http://s1187.photobucket.com/user/BobinNH1/media/20160229_013458.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zps55780313.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpsfmvpfiwq.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpspnmvbllq.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpsmjbqe2be.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpscgh65e0m.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpsjgimtsfu.jpg.html)
![[Linked Image]](http://i540.photobucket.com/albums/gg342/steveberrett/4138309E-1E79-49BC-9E94-A1B4E8167A3C_zpsqzsijftg.jpg)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zps2ym79uvv.jpg.html)
![[Linked Image]](http://i540.photobucket.com/albums/gg342/steveberrett/D86E4979-7DBE-485F-A467-8AE73F52A69B.png_zpsfe83xauj.jpeg)
![[Linked Image]](http://i540.photobucket.com/albums/gg342/steveberrett/5D49A000-BE3B-4E5B-AC4A-C4C0DB2E30FB.png_zps7xbyf24q.jpeg)
![[Linked Image]](http://s1187.photobucket.com/user/BobinNH1/media/20160121_153444_2.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpsjhhrqfc4.jpg.html)
![[Linked Image]](http://s1187.photobucket.com/user/BobinNH1/media/20151220_132939.jpg.html)
![[Linked Image]](http://i757.photobucket.com/albums/xx220/ClarkM/One%20Flew%20Over%20The%20Cuckoos%20Nest%20%20you%20didnt%20weigh%20the%20chain%20did%20you.jpg)
![[Linked Image]](http://s1187.photobucket.com/user/BobinNH1/media/20160405_143044.jpg.html)
![[Linked Image]](http://s1163.photobucket.com/user/les760/media/9BD94071-D350-4FC3-A9AC-278C3E695AC9.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/FAC6A9BB-9EB2-4958-9674-CCE6880D5151_1.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/B834B307-60A0-4E45-AE73-1B13EECF498A.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/P1010422.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/P1010424.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/P1010425.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/P1010427.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/P1010428.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/BAB4E2E1-ABE5-43EE-B1B6-8DDDC5D08167_zpsrs532tes.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/CCEDE5D8-153B-4DAA-A5A0-55C1986C8524_zps7uqddc4s.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/7A9E7C70-BB2A-4021-9869-C96EA58AB83F_zpsquapiyxo.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/5C06075B-E899-46D0-B69C-C4F11BB67462_zpssvhgqh4l.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/82C1EBA7-C992-437D-A5F6-72927D4A5AF4_zpshpcjlc7f.jpg.html)
![[Linked Image]](http://s723.photobucket.com/user/beretzs/media/RIFLES/Model%2070%207mm%20Mashburn%20Super%20Magnum/FA3C07AC-584E-4AC6-AA42-88AE62794AEE_zpsk8m66ze7.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpsodallivp.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpscdbnv0fy.jpg.html)
![[Linked Image]](http://s757.photobucket.com/user/brockel/media/Mobile%20Uploads/image_zpsfyrc3mo4.jpg.html)
![[Linked Image]](http://s379.photobucket.com/user/rcamuglia/media/3F45F8DF-B1F6-4CAB-844E-78849428FF8C.jpg.html)
![[Linked Image]](http://s575.photobucket.com/user/dustinschilling/media/image.jpg2_zpses8jg63d.jpg.html)
![[Linked Image]](http://s575.photobucket.com/user/dustinschilling/media/image.jpg4_zps1o9dyhrr.jpg.html)
![[Linked Image]](http://s575.photobucket.com/user/dustinschilling/media/image.jpg3_zpsxktmkg3l.jpg.html)