Home Forums Hunting & Shooting Custom Rifles & Wildcats Here's my 7mm Mashburn, show us yours!

8 lbs or less scoped is my goal as well.

Deciding between a big 7 or a 300 Win Mag.

I know Bob always preferred the big 7.

I still have a pile of 7mm Dakota brass onhand, but that would involve work on the bolt face, etc.

Mashburn or Nosler if I go with a 7mm.

I do have a 7mm Rem Mag I built on a M70 classic edge. Sub 8lbs with a Swaro Z5 3.5-18 in Talley Lightweights. One of my "core 4".

Shoots the 160 Accubond VERY well at 3100, so maybe what I'm looking for is already in the safe.

What load do you use to get 3100?

I like the 7mm's myself in a sub 8 pound rifle they aren't real unmanageable with the top end loads. You're current 70 is pretty danged close to perfect in my opinion if you like it. If It shoots well now, it isn't going to shoot less well as a Mashburn either. It's almost cheating to stick a 3.6" mag box, shorter bolt stop and rechamber a 7mm Rem Mag to see if you like it. It is what I did for my first one and I decided I liked it enough to have Kevin Weaver build me one I really liked.

The Mashburn is exactly like John55, Joel and Gunner describe it. For my first one I used plain old RCBS FL dies and simply ran Hornady 300 Win Mag cases into the die and when I pulled them out they were 95% ready to go. I used Dober's load of 65-67 grains of IMR4350 with a 139-145 grain bullet and formed all of my brass. My only issue was once neck donuts started appearing. Bob never got them, Gunner hasn't ever got them, but with the 3 Mashers I have worked with, I got them. It is super easy though, a quick ream with an electric drill and they are gone forever.

I got the Redding dies when I got the 2nd rifle and that's all I have used to this point. John and Joel have the Whidden dies made for their chambers so they have gotten away without donuts thus far.

Dober's had 7 barrels on his Mashburn over the years and doesn't believe in the donuts and he's filled arks full of elk, bear and deer with his with 120 Barnes through 175 Semi Spitzer Partitions.

I can't remember if PF76 has dealt with donuts or not in his gun, but honestly it isn't that big of a deal if they show up.

The beauty of the Mashburn is ANY of the 300 Win Mag cases will work really well. WW used to be the gold standard. I used alot of Hornady, but has been using the same 50 RWS cases I formed back in 2017'ish. God knows how many loads of 175's over 83.8 grains of RL33 I have on them, but it is going on 6-8 firings, I anneal them everytime and they just won't wear out. ADG now makes 300 Win Mag brass which is probably as good or better than RWS so the amount of great brass makes the Mashburn pretty appealing to me and its just outside the ballpark of a 28 Nosler. I also don't think it needs a barrel longer than 24" myself. My old Winchester that was rechambered was just as fast as this Bartlein and just as accurate with almost the same charges of powder.

I just finished up load work for my cousins 28 Nosler and I used H1000 for 175 Partitions and averaged 3110 for speeds. I could've used Retumbo or RL33 and probably gained 100 FPS but on that one, I think it needs the 26" barrel to get those speeds, it recoils more, and is a bit heavier rifle and you lose 1 round typically in the belly. Any of our Win Mag Classics will feed and function like they have eyes with the Mashburn case, while a 28 Nosler will be more work to get them to feed and function that way.

Sorry for the babbling, just my thoughts on it.

300 Win Mag with a 1-8/1-9 barrel is pretty easy if you don't want any of the extra HorseSh*t if it is set up to seat the longer bullets to maximize case space. John55 has worked with 3 of Weavers recent 300 Wins and can chime in with his thoughts on them to give you an idea of what he is getting.

Here is Gunner's Mashburn Super





And his latest kill with the Glock...

Mrs. McGregor’s Pie!

LOL, Thanks Big B, that little NF tracks pretty true huh? waiting on the rain to clear to try for 900, that damn rabbit was eyeballing Wifes garden just outside the back gate, the 200gr Lehigh over penetrated, look at the hole in the ground.

No pie Mr. Douglas, too late in the year for eating, chunked it over the fence, the Rotts were playing stretch arm strong with him when I fired up the ATV and left ; ]

Yeah, you’ve got a killer set up as well Gunner.

Careful now fellas, we’ll be pushing NYrifleman over the edge here soon

Thanks, and Yes, he'll be flexing some plastic or rolling ink in no time!

It's either 66.0 or 68.0 7828SSC, I'd need to check my notes. Shot over my LabRadar chrono.

I'm going to load some 175 Partitions over Retumbo and RL26. Should get 2900+ I would think.

If anyone has a good load, chime in!

If the 175 shoots well with acceptable velocity, the decision may be made for me.

You know, I had a Masburn in the safe at one point.

But that 7mm Rem and the 7mm Dakota I had in the safe at the time made it redundant so I flipped it before I ever shot it.

If a 7lb Mashburn on an M70 action, which is proven shooter came up for sale here I'd be hard pressed not to jump.

Beretzs, not babbling - I'm enjoying the conversation of like minded individuals. Carry on!

Looks like a beautiful thing to spend your money on.

Welp, I found the limit of a 160gr Accubond with cannelure at 900 yards, didn't take a pic, too embarrassing, those things river boat paddle wheeled themselves into a 3 shot 24 inch group, that said and learned, I moved my bench back to it's old spot and had at the 500 yard gong, in crazy winds, three went into a bit under 4 inches, that I can hunt with, I don't know where that bullet really came unwound, but it's somewhere North of 500 to 900 yards.

Need to experiment with big 180 ish grain bullets for real longer range shooting/hunting, the 8 twist and 3200 fps really walked that fine hunting bullet, the same bullet without cannelure may have flown better, pics on the way soon.

Appreciate the response Joel.
I wonder what it is about the edge fill that would make the rifle more finicky? I suspect it would be more than just weight, as the weight differential isn’t really all that great.
Having said that, I appreciate you posting the blank weight of your edge shell/standard fill. I picked up a Legend standard shell/mag fill on here a while back for a planned 375 build; that blank weights 35 oz (!) and I’m starting to wonder if I really want to be that heavy on the stock ...
Your experience with the shrike should translate well to the legend, as they are the same pattern. How long was it getting the shrike if I may ask?

I'm one of the few who doesn't care for the ergonomics of the Echols Legend.

Much prefer the McMillan Bridges.

Waiting on an Edge for my RUM.

Pathfinder,

That's a nice looking build. What are the particulars of that barrel (length. contour...)?

FWIW - I just weighed an Echols legend edge shell, standard fill I have and in its out of the mould and unfinished state it weighs 28 ounces.

My last 2 Legend blanks were all Edge and weighed 25oz each. My latest blank that is Edge shell and standard fill weighs 27oz. D’Arcy has told me on several occasions the blanks have become heavier since inception. Early all Edge blanks weighed 19-20oz.
IMO, the reason an all Edge stock can be a bit finicky is due to barrel vibration/harmonics. I’ve not seen it in standard calibers like 270 or 30/06 but once you get to 300 mag levels it’s more of a possibility. For a 338 or larger I use magnum fill. A bit of extra weight doesn’t bother me as it helps with the recoil.

I also don’t mind the extra oz of standard fill weight.

Interesting to hear I’m not the only one with edge shell/standard fill. Must be a good idea!

Thanks. It’s a 24” #2 Douglas

My MSM is heaviier than Pathfinder’s and Farese’s, in spite of virtually identical components. With it’s all Edge stock and 6x36 scope it’s just under 8.25 pounds. My 300 Win mag at same weight is much more of a handful off the bench. 175s at 3000 are no match for 200s at 2975.