Like the topic says can you neck down 325 wsm brass to 7wsm?? I found some yesterday and was curious as my buddy has one
- Thread starter Aimsmall55
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I used to have a 325 and still have a 270 WSM and have necked 325 and 300 down to 270. It will need a bit of a trim, and maybe a neck turn, but it will work, just takes a bit more work to have good consistency with it is all. It's not going to be precision brass by any stretch, but plenty good for hunting purposes.
Edit: see next post, I had not noticed that about the 7 WSM being singularly different in that aspect from the rest of the factory WSM family.
Edit: see next post, I had not noticed that about the 7 WSM being singularly different in that aspect from the rest of the factory WSM family.
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The 270wsm, 300wsm and 325wsm share a casehead-to-shoulder datum length, but the 7wsm does not; the 7wsm is ~.040" longer. This makes it impossible to accidentally (or purposefully) chamber a 7wsm cartridge in a 270wsm chamber, which would be ultra-bad news. Obviously, the 300wsm isn't going to fit a 270wsm on account of the .030" diameter different of the bullet, and the same goes for the .325, but because the 7mm (.284") and 270 (.277") bullets are so close in diameter, the headspace was changed.
Anyway, 270, 300 and 325wsm can be made into 7wsm brass, but it is not as simple as simply necking it appropriately. To do so would be like bumping the shoulder of case back .040" and firing it. WAY WAY excessive headspace - dangerously so.
Instead, you'll either need to load the bullet really long, to ENSURE the bullet is good and jammed. That will make sure the casehead is in full contact with the boltface on firing. That ensures all the case stretching occurs up at the shoulder, and not down by the web.
The other technique for this, which is superior, is the "false shoulder" method. You would neck the 325wsm case down appropriately for 7mm, BUT ONLY DOWN THE NECK FAR ENOUGH TO LEAVE PART OF THE NECK LEFT BIG. The idea is to leave part of the neck "big" so it contacts the shoulder of the chamber, providing a slight "crush fit" of the cartridge in the chamber. This will correctly locate the cartridge in the chamber.
Interesting, I never caught that before, since I never loaded the 7WSM but had loaded all 3 of the other factory WSM's. Thanks for catching that.
