Forming the 7MM Super Mashburn

Nice round.

I went through the same process, but in 6.5mm. I have a 6.5-300 Win Mag, which is a 300 Win Mag necked down to 6.5mm, with a few other changes such as neck length and sholder angle. Gives a bit more MV, or a bit less pressure at the same MV (as you prefer) than the 264 Win Mag. Fits nicely in a standard action, unlike a 6.5 STW or 6.5 RUM.

The next step up from the 7mm Super Mashburn in a standard action would be a RUM case necked down to 7mm and shortened to 2.620", like the 300 Win Mag and its wildcats. I did that for the 8mm, hence the "8mm ARP" - my own "Vanity Round".

Now before anyone rushes out to be the first to do it in 7mm, forget it - it's been done, and there are no new wildcats. Guys might change the shoulder angle a few degrees, or body dimensions by a few thou, but the instant a new cartridge is announced, guys all over the place start ordering custom reamers and that occurred years ago for the RUM cases.
 
Doc M said:
If ever there were an answer to a question nobody ever asked, I think this cartridge is it.

But hey, the great thing about personal choice is that you can fill your boots with whatever you like - so good on ya for experimenting.

All I see is a rifle hard to find brass for, shooting virtually identically to the 7RM which you can't spit without finding in the most back-woods of gun stores.

-M
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By what you say, we would be better off shooting a 30/30, 303, 308, 270, 30/06 or 7RM.

I'd have to sell 3/4 of my guns if that was the case. :(

.
 
Doc M said:
Send me a box of FACTORY 7MSM in the mail and I'll apologize.

No forming, no screwing around - just find me some factory loads, send 'em to me, and I'll apologize.

I love reloading as much as the next guy, but the practicality factor isn't weighing in on the side of the MSM.

IMO, the availability of common factory cartridges that can perform just as well (or within damn close spitting distance) of this loading make it not worth the hassle.

WITH THAT SAID...

... if you like playing with it, that's your prerogative - and more power to you! :)

-M
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Brass and Factory loaded ammunition are two very different things. Apology accepted.:D
 
Ready to fire form.

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I think it's a great project and an excellent round for hunting. Personally I like these kind of chamberings because no one that I hunt or shoot with has them. I've got a 218 Mashburn Bee, a 350 Mashburn Super mag and a 25/06 Ackley, not because I couldn't use a factory chambering that was comparable, but because I can, and I enjoy doing it.
 
If I wanted another 7mm wildcat, (and I don't) I would get a 7mm-375 Ruger built.

Then I could say stuff like "smooth beltless feeding" and "high efficiency" and quote shoulder degree....

While getting the same performance as a 7STW that I bought off the shelf. :p
 
I was wondering if you could help me ? I have a model 70 build 77 mm mashburn it was a gun that was given to me unfinished ,an old friend passed and here I am , I’ve tried to make casings for the rifle have the die set but still can make them chamber . Wonder if a Fire Forming might help and where can I purchase such a thing .
John F
johnfillier@hotmail.ca
 
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