Can 7mm STW cases be resized to 300 H and H

[pacobillie]

I went to a gun show on Sunday December 12, and I picked up a 100 cases of 7mm STW brass. I do not have a rifle chambered for that cartridge (7mm STW), and I am not planning on getting one, which leaves me with two options: selling those cases on the EE, or resizing them to another chambering, to use in one of my other rifles.

My only magnum length chambering is 300 H&H Magnum. I have a set of Redding FL dies. I do not doubt that the mouth can be opened to .308", but I am a bit more skeptical about resizing the case body, since the 300 H&H has a lot more taper and very different shoulder. Has anyone tried making 300 H&H cases from other magnum length cases such as 8mm Magnum, 7 mm STW, or 300 Wby Mag? How well did it work?

Looking forward to your answers.

 

[alberta tactical rifle]

When 7 STW was new you had to neck down and fireform 300H&H brass, so no reason this could not be done in reverse.

 

[Eagleye]

It is possible to do, but you may lose an occasional case to "folds" in the shoulder area of the cases.
Even with the fold, these cases can be used, but a crack will form at the fold fairly quickly.
Do not put lube on the shoulder area of the case. Lube there encourages the folds. Dave.

 

[sharp shooter]

If anything I would anneal it first if you have the resources.

 

[SuperCub]

I asked a member (with more experience than myself) here a similar question.

I have some 300H&H brass that has been fireformed to 300WBY and wanted to reform it back to H&H. He told me that it wouldn't work well and described similar to what Dave said.

I never bothered.

 

[Potashminer]

When 7 STW was new you had to neck down and fireform 300H&H brass, so no reason this could not be done in reverse.

I do not own one, but had to research for another fellow having difficulties - I think back in the day that Layne Simpson was forming his "new" 7mm STW from 8mm Rem Mag. Later he had some help from Kenny Jarret. Not real sure where the 300 H&H came from, but no doubt would have worked to make 7mm STW?

 

[billdick]

If you have a 300 H&H RCBS trim die use it to size the body. It'll be absolutely no problem in a trim die and would work in a sizing die too but you'll have to go slower. The neck will easily go up to .30 cal

 

[burnt_servo]

it will defiantly work , and i would anneal the cases .
are they new or fired ?

btw what did you want for them ?

 

[pacobillie]

it will defiantly work , and i would anneal the cases .
are they new or fired ?

btw what did you want for them ?

They are once fired, but all are clean, sized, trimmed to length and chamfered. You may PM me with an offer. They are all Remington-Peters headstamp.

 

[track]

My first question is: Why? Why did you purchase something that you really didn't need? Why go to all that work to resize 100 brass and to weaken the integrity of them? I would suggest to move forward, sell the brass and go purchase a couple of boxes of Nosler brass for your 300 H&H.

 

[stubblejumper]

You should have no problem selling them, there are usually people looking for 7mmstw brass, even if it is once fired.

 

[pacobillie]

My first question is: Why? Why did you purchase something that you really didn't need? Why go to all that work to resize 100 brass and to weaken the integrity of them? I would suggest to move forward, sell the brass and go purchase a couple of boxes of Nosler brass for your 300 H&H.

Because I got them for a song, and I know that there is someone out there willing to pay more than the price of a song, if I cannot make use of them.

 

[dan belisle]

I do not own one, but had to research for another fellow having difficulties - I think back in the day that Layne Simpson was forming his "new" 7mm STW from 8mm Rem Mag. Later he had some help from Kenny Jarret. Not real sure where the 300 H&H came from, but no doubt would have worked to make 7mm STW?

It does. First 7 STW I built was back when it was a wildcat, and 8 Rem Mag cases were thin on the ground. 300 H&H cases were fairly easy to find (keep in mind this was pre internet), so I used those. they were a tad short, but worked fine. - dan

 

[Eagleye]

I had one of the first 7mm STW rifles in the area. I had a 7mm Rem Mag rechambered to the STW.

There was no head stamped STW brass available at the time, so I made a bunch from 8mm Rem Mag.
Others I made from 300 H&H, 375 H&H, 300 Weatherby and 340 Weatherby cases. All worked just fine.

On a lark, I took one of the reformed 375 H&H cases [WW Super] and sized it back to 375 H&H in
steps of the expander [30 cal, 8mm, 35 cal and finally the 375 H&H FL sizer.] It worked OK, but a bit
of fiddling. Dave.

 

[pacobillie]

To close the loop. I attempted to resize one of the cases, without annealing. In spite of generous lubrification, I felt a lot of resistance, and the case jammed in the die. I was able to get it out, but will not try again. The 7 mm STW cases are for sale on the EE, if anyone is interested.

 

[MRP]

If you don’t try you’ll never know. I’ve made 300wsm from 7mmwsm. Anneal first.

 

[dan belisle]

If you don’t try you’ll never know. I’ve made 300wsm from 7mmwsm. Anneal first.

And use plenty of imperial case lube. - dan

 

[pacobillie]

If you don’t try you’ll never know. I’ve made 300wsm from 7mmwsm. Anneal first.

That would be a much easier one, i.e same overall case dimensions, different neck size.

I have done plenty of that myself, sometimes to a much greater extent. 9.3x57 from 8x57 and 30-06; 257 Wby from 7mm Wby and 7mm Rem mag; 35 Whelen from 30-06.

7mm STW has a very different shape, as compared to the 300 H&H: less body taper and much sharper shoulder.

 

[Why not?]

Brief sidetrack: 300 Win Mag can be resized and fireformed to 300 H&H. Did it a couple of times just to see if it would work.



It does. The neck ends up quite short, but still hold bullets secure enough to use safely.

This case has been fired with a stiff 180 gr load. You can see where the original 300 Win Mag shoulder is located in the 300 H&H.

Ted