7mm IHMSA back to .300 Savage

atuna69 · Dec 27, 2019

I recently bought a bunch of .300 Savage brass. There was a fair amount that were loaded and needed to be broke down for the components. I thought they looked strange as the bullets weren't seated anywhere near the cannelure. Short story long the brass was necked down and resized to 7mm IHMSA. My question is can I size it back to .300 Savage? If I annealed it and ran it in the sizing die would it be pliable enough to take a .308 bullet from .284 and put the shoulder back where it needs to be? If I just need to junk them I will, just thought it might work.

Member 5605 · Dec 27, 2019

Maybe.. you'll have a thin neck. Probably won't get much more than a couple firings.

Anneal first though, you may have some resilient brass.

ageingstudent · Dec 28, 2019

atuna69 said:
I recently bought a bunch of .300 Savage brass. There was a fair amount that were loaded and needed to be broke down for the components. I thought they looked strange as the bullets weren't seated anywhere near the cannelure. Short story long the brass was necked down and resized to 7mm IHMSA. My question is can I size it back to .300 Savage? If I annealed it and ran it in the sizing die would it be pliable enough to take a .308 bullet from .284 and put the shoulder back where it needs to be? If I just need to junk them I will, just thought it might work.

You should be able to go back to .300 sav with that. Like dyg said it might not last very well. What kind of rifle are you shooting the .300 sav out of? Savage 99? I have a Remington model 81 in .300 sav. I form brass for it out of 7.62x51 and it works better than either .300sav or .308 commercial brass. Lots of neck cutting and trimming

. It's a real labor of love.

atuna69 · Dec 29, 2019

I'm shooting a old 99E. Thought I would use I it for deer if I don't draw my muzzle loader tag. I thought it would make a cool little project to try and save the brass.