Home Forums Hunting & Shooting Long Range Hunting 7mm Wby and LRAB results...........

Also, I loaded 76.0 grains of RL25 for an average of 3,160 mv.

Good accuracy as well. So, I can boast my speed up just like the Mashburn and still go comfortable at 3,080 too.

Nice....:)

rosco: I don't need any reassurance on the Mashburn....I see three of them shot regularly over a chronograph.And I get feedback regularly from people who also own and shoot them.Seems everyone ends up in about the same places velocity wise.



The only one's who seem to need "reassurance" are the people who don't own one and have never loaded for it.

My suggestion is that folks go load for the 7 Rem Mag in standard and long throat versions,the STW, the Mashburn, and the 7mm Dakota.I already have and know what I like..toss in the 7 mm Weatheby if you like but i won't...the case is too small for what I want,and I don't want to rely on freebore and maxed pressures to get the velocities I want.

If you want to to compare the STW to the Mashburn,you have my loads with H1000; compare them to loads for the STW in the Nolser manual.I an not at all inconsistent.

SU the Mashburn will beat that by 100 fps comfortably.From a 24 inch barrel....they are most definitely NOT the same.

SU35, thanks for the report. Despite wind your horizontal looks good. Initial indications are that the BC's are holding up. Update us when you longer. I hope I beat you to it!

BTW, love your range. Its slightly different down in the southeast. We have to cut lanes just to get a 100.

Bob, you're a trip!
If I ever need a cheerleader to champion a cause, I'm gonna call ya!

Actually, Bob, is among the most credible and articulate regular posters here on issues concerning hunting rifles, their appropriate uses and he bases his opinions on a level of ownership and use of a number of rifles that, to my mind, gives them the authority that few others here really have.

As I have posted in the recent past, Bob, reminds me strongly of the late Allen Day, who was also a poster for whose comments and real knowledge, I developed the greatest respect.

These guys, both somewhat younger than I and both articulate and rational observers/commentators on these topics,were/ are why I log onto the "Campfire" as I usually do and I wish we had more such genuine experts. I learn from Bob in at least 75% of his posts and I am not exactly a novice as well as having FAR too many bloody rifles to mess with.

So, while I totally agree with "MadMooner" here, I also read Bob's posts to learn serious aspects of our mutual obsession with fine thundersticks.

+1

The pearls of wisdom one finds on the Fire are priceless and well worth the effort of having to sort thru the "other stuff".

DF

Kute- I agree 100%.

Wow, Bob! Are you getting 3,260 mv shooting 175's? I shoot a 24" barrel too.

Cause that is what I am shooting, 175 grain bullets.

I thought I saw where you were shooting 175's at less than 3,200.

Does this imply that by seating bullets deeper in most non-Weatherby rifles, that velocities can be increased (with the given trade-offs stated)? It seems that quite a number of loads with slow powders do not use the full case capacity so there is often room. If this is so I would guess this would only hold up to some point.

David

The SAAMI drawing for the 7mm Wby. shows about 3/8" of freebore, which is way past the change you could get with reasonable seating depth variations.

John,
My generAl thoughts re pressure testing: the gains reported with wildcats are due to 70,000+ pressures. The prime example is the 243 AI. Would love to see an "apples to apples" comparison.

Bob,
I will willingly join the Mashburn Society when a factory produces ammo and brass. I am just too lazy to form cases now days. Besides I don't need more than 3150 because of the mid range rise problems and with today's bullets I don't need more than 145-150 grains. If more is required then get a 375 H&H.

mathman,
In my rifle, some Remington factory ammo was a bit over 0.1" from the lands. It seems straight forward to seat longer bullets such as 160 ABs another 0.1" or maybe 0.2" deeper.

Not quite 3/8 but maybe enough to have the stated effect?

What I don't know is:
* Is seating depth relative to the length that touches the rifle a measure of freebore?
* Is there a minimum COL established like a max COL?


David

I believe that he can! Do you think that the extra throat will hurt anything? I will be going from being able to seat the bullet to 3.53 to 3.68. Is that too much?

Ain't that the truth!!

This is 100 percent correct, many shooters believe the bullets jump a canyon when in fact they just slide through a very tight tube, I have measured all my Bee rifles and the bullet is very tight in the freebore tube.

David,

Though the pressure curve usually flattens when bullets are seated deeper in a conventional, short-throated chamber, there are problems that occur. First is that accuracy often suffers--though not always. Second is the shank of the bullet may end up too far down the neck to hold securely. Third is the powder charge often can't be increased because the rear end of the bullet takes up more room.

Rick,

I believe you're right about the 70,000 psi on wildcats, but we don't need to pressure-test any of the factory loads. The SAAMI maximum average pressure for the 7mm Weatherby and 7mm STW is 65,000 psi, just as it is for the 7mm SAUM, 7mm WSM and 7mm RUM. So the velocities they're getting, whether with factory ammo or SAAMI-member handloading data (such as Nosler's) have been pressure-tested at not more than 65,000 psi.

All we really need is for some 7mm Mashburn enthusiast to loan their rifle and handloads to somebody with a Pressure Trace or other strain-gauge setup, and we can find out what the pressures are.

lol i'd play if someone within reasonable distance of northeast pa had pressure testing equipment

Rick I know. I understand all that.

It's easy enough to stick a 145 LRX in a Mashburn. I could do that with a FF load,get 3150,and go hunting.Chuck used that bullet this year in his rifle

I have Bitterroots and will get around to other stuff when those are gone.


I have played around with free bore,and long throats, barrels with over sized grooves etc and seen results.These days I lean more toward "buying" some additional case capacity if I want more velocity. In putting this rifle together I did not want a cartridge that depended on any tricky barrel stuff to get the velocities I wanted....I went with the bigger case...so I got a Mashburn. I was just coming "off" a Dakota and knew what one wold do the other one would.

No doubt a pressure trace would tell a story. I would not be surprised to see my Mashburn loads at 65,000 psi but if so I don't think it's a problem to load a Weatherby that hot and not a Mashburn. If it read 70,000 psi so what...I'll back it off and still get plenty of velocity....I could even the playing field by giving the Mashburn 3/8" freebore, too....no trick involved at all.

Page sent his rifle to Remington for pressure testing and chronographing,and that load of his gave 3050 with the 175 NPT...yes I know todays pressure testing stuff is better but still someone measured it at some point.Beside we have better powders now... I can run a 175 gr at that velocity level in my rifle all day long using H1000 without ill effect. This is about 100 fps better than a 7 Rem Mag with a top load with that same bullet.

(Friend Kent D who used to post here is running all over North America with his rechambered Rem 700 knocking off everything from a record book desert sheep to elk and other stuff with a 175 TBBC at 3040 from his rifle.He's only taken all NA species 3 times.)

After a few firings my cases are not showing any sign of primer pockets opening up.

I have had exactly one "snafu" in all the load workup with my rifle. A load of 78 gr of Retumbo and a 160 gr NPT came over the chronograph at 3330....I saw the numbers and was afraid to open the bolt...but there was no ejector mark, no blown primer,no stiff bolt lift....I discarded the case and immediately knew it was TOO hot just based on the velocity.

Where did I get that load? I had backed off 1.5 gr from the top end load in the Nosler Manual for the same bullet with the 7mm Weatherby...so yes I think John is right when he says the free bore flattens the pressure curve.But no one will convince me the 7mm Weatherby is not being loaded to the gills to get what it gets ......it also goes to show what a tremendous safety margin I have when running a 160 gr at 3160-3200 fps.

Doc Bill on here and and others have used RL25 to get 3200-3250 with 160's...I would not want to push beyond that.I have seen enough 160 NPTs ad 160 AB's fly down range without a whimper at those velocities. from two other barrels here using RL25 and Retumbo.

I don't know what the big deal is anyway.....you'd think the cartridge were some new invention. .

It's been proven world wide in Page's hands with a 175 gr NPT at 3050 in the tropics of Africa and India,the cold of North America,New Zealand,the mountains of Central Asia, on 450+ head of BG,...... and by Hagel on everything here in North America at the same velocity levels, including grizzlies,elk, and Alaskan Yukon Moose.It probably has more world wide "experience" on more types of BG than any other 7mm magnum,factory or wildcat, and it's as thoroughly proven in the world wide BG hunting arena as the 300 Weatherby magnum (and some others) in terms of reliability on a wide variety of animals...I am certain if there had been any "problems" with it,those gents would have uncovered it.

My only regret with the cartridge is that I didn't build one 30 years ago.Doubt I'd have used anything much else for a lot of my hunting.