Short action 7mm with Mag bolt face using 300 WSM brass.

[Patriot308]

This is where I am at and where I want to go I had a REM 700 with a 26” Kreiger stainless barrel .308 1-11.25 twist. Had issues with it after I had a local smith work on it, sent to GA Precision, opened the bolt face up, M-16 extractor, trued, Hawkins bottom metal, and they rechambered it to 300 WSM. It’s shooting light out with a 178gr ELDX 3120 with R-17 and descent 190gr Sierra Match.
I want to rebarrel to a 7mm with magnum bolt face, that I can run 175-180gr and use my $400 worth of magazines, and I have over 1000rd of 300 WSM brass. I think I can use my short mag brass to make 7mm SAUM, 7mm SS, but I am very interested in the 7-6.5 PRCW, but not sure if I can use my brass to make them. I know PRC brass is more available, but I don’t want to re invent the wheel, because of the amount of good brass I have.

 

[SKWERLZ]

7/300 WSM is a great option, bit more case capacity than 7 saum.
I wouldn’t bother trying to form 300 WSM into saum or prc because you gain nothing over the 7/300WSM and the fat .550 base will fight you especially to 7/6.5prc.
7/300 gets you that bit of room to really shine with H1000 that the prc and saum don’t if you can’t find R26 and H4831 will be awesome for the 160-170 grain bullets.

 

[wyshadow]

Not sure what you're asking but if you want to neck down your 300 wsm to 7mm, the answer is yes. I use two neck bushings to size down. I use to turned my necks after sizing down but I found out you could just shoot it and trim the brass. You'll notice you will have to trim a lot brass off at first but the neck brass will slow down if that makes sense. Much faster and easier this way

 

[Patriot308]

Not sure what you're asking but if you want to neck down your 300 wsm to 7mm, the answer is yes. I use two neck bushings to size down. I use to turned my necks after sizing down but I found out you could just shoot it and trim the brass. You'll notice you will have to trim a lot brass off at first but the neck brass will slow down if that makes sense. Much faster and easier this way

No 7mm WSM will no allow me to use good high BC bullets in my short action, it the same issue I have with my 300 WSM. I need a shorter case that can fit a long BC projectiles, 7mm SAUM, Sherman Short, or the 7-6.5 PRCW are my options. Just need to know if I can use my stock pile of 300 WSM brass, or if anyone has been using it for these loads.

 

[CJ6]

Another option.....sell your stockpile and buy the cases you need

 

[alf]

I think I can use my short mag brass to make 7mm SAUM, 7mm SS.

I once thought that too, & promptly crack my die.

 

[Patriot308]

I guess I need to give more information, my overall length with the 300 WSM or 7-300 WSM is the limiting factor. My range is a mile and with my 178gr out of my short mag is falling on its face at about 1400 yards. I can’t run the high BC bullets I need to shoot beyond that, in my Short Mag with my short action. The 7mm SAUM or Sherman Short is the direction I am heading, to be able to use high BC 7mm bullets, to cover the distance I am wanting to shoot. Main question is has anybody been using 300 WSM brass to make 7mm SAUM, or Sherman Short brass, I think there’s going to be an issue with the 7-6.5 PRCW.

 

[SKWERLZ]

No 7mm WSM will no allow me to use good high BC bullets in my short action, it the same issue I have with my 300 WSM. I need a shorter case that can fit a long BC projectiles, 7mm SAUM, Sherman Short, or the 7-6.5 PRCW are my options. Just need to know if I can use my stock pile of 300 WSM brass, or if anyone has been using it for these loads.

He’s talking about the 7/300WSM
A good bit shorter body and longer neck for the7/300 wildcat over the 7WSM

 

[SKWERLZ]

I guess I need to give more information, my overall length with the 300 WSM or 7-300 WSM is the limiting factor. My range is a mile and with my 178gr out of my short mag is falling on its face at about 1400 yards. I can’t run the high BC bullets I need to shoot beyond that, in my Short Mag with my short action. The 7mm SAUM or Sherman Short is the direction I am heading, to be able to use high BC 7mm bullets, to cover the distance I am wanting to shoot. Main question is has anybody been using 300 WSM brass to make 7mm SAUM, or Sherman Short brass, I think there’s going to be an issue with the 7-6.5 PRCW.

Even on my 7SAUM I run 180 or 190 Berger’s beyond SA mag length so I single feed them.
I can barely get the 180 at mag length but the loss of case capacity hoses you unless you have R26 or want to get spooky with 4831.

 

[Patriot308]

Another option.....sell your stockpile and buy the cases you need

I have thought about that but I am going to keep my barrel for the Zombie’s and the amount of bullets I have in .30 cal setting on the bench. Every thing was great when I was shooting at 1000, but started shooting farther distances, and screwed everything up.

 

[Patriot308]

I once thought that too, & promptly crack my die.

I have made a bunch of 6.5 CR brass from 243 Win when I was in Alaska when I couldn’t find 6.5 brass, never had an issue, and have 5 loadings on 350 brass.

 

[SKWERLZ]

I have made a bunch of 6.5 CR brass from 243 Win when I was in Alaska when I couldn’t find 6.5 brass, never had an issue, and have 5 loadings on 350 brass.

Big difference than trying to squeeze a .550 base to .532

 

[Patriot308]

Big difference than trying to squeeze a .550 base to .532

The SAUM has a .550 base if, I recall.

 

[SKWERLZ]

It does but really doesn’t offer anything the 7/300 WSM doesn’t.
If you really want heavies in a short action magazine the 7SS might be the ticket but I’m not sure how well it forms from WSM brass.

 

[Patriot308]

It does but really doesn’t offer anything the 7/300 WSM doesn’t.
If you really want heavies in a short action magazine the 7SS might be the ticket but I’m not sure how well it forms from WSM brass.

Definitely going to research the7/300 more and I am running MDT magazine and I can run up to 2.955 OAL. Thanks for your help.

 

[J.d. Popkes]

Any of these options on a short action, in my opinion, is suboptimal. You should be interested in case capacity and seating long, out of the donut area, and fully harnessing what the case can provide. A saum in a short action with 180’s to me is hobbling it and asking for problems.

 

[dk17hmr]

If you can use up to 3.240" with your mag what's wrong with your 300? Shoot a heavier bullet.

My 300wsm with a 30" pipe is shooting a 208gr seated to 2.960" at 2950fps (it'll go faster). 1 mile is very doable

 

[Idaho-Lefty]

Definitely going to research the7/300 more and I am running MDT magazine and I can run up to 3.240 OAL. Thanks for your help.

The 7mm-.300 WSM or, 7mm-.270 WSM ( Same thing, just different, "starting Case" ) IS, very popular for, 1,000 yd Comp's,. in the UK and Canada !
Or just sell your, .300 WSM Brass and Buy, the 7 SAUM, ( ADG, 7 SAUM Brass, is Excellent ! ) if wanting, a Bit shorter,.. case / Cartridge.
But both, are Fine,. Long Range, Cart's, as Noted above, the 7mm-.300 wsm will Hold, a Few grains, MORE Powder.
A Medium or, Long Action is, Needed,.. IF, the 7-.300 WSM with, YOUR Choice of, Bullet, doesn't, Fit or, Feed, in Your Action !

 

[Patriot308]

If you can use up to 3.240" with your mag what's wrong with your 300? Shoot a heavier bullet.

My 300wsm with a 30" pipe is shooting a 208gr seated to 2.960" at 2950fps (it'll go faster). 1 mile is very doable

I checked my mags OAL is 2.955, my barrel twist is a 1:11.25, which is a factor. I am running a 178gr, ELDX and they are shooting lights out, I have tried heavier and rifle doesn’t like them.

 

[wyshadow]

IMO (and you know what they say about opinions) if you are wanting to take advantage of the longer/higher BC 7mm, I would use a long action or a magnum action. I struggled with my 7 WSM build in a SA and right now it's shooting great. From what I know now, I would've never chosen the 7 WSM and would have looked at the 7 PRC or the 280 AI with a longer freebore.