Home Forums Reloading Big Game Rifles Can I neck size a .30-378?

I know I can, but is it recommended? I neck size all my smaller cals and rarely have to trim. I've heard that neck sizing cartridges used for hunting can dislodge from recoil. Any one have a take on this?

If you gotta quiz the masses,you're better bumpin' that shoulder....................

Supertrucker,

Its called bullet setback when a bullet moves or shifts within the case due to recoil while resting in the magazine. Its a matter of neck tension which may or may not be related to neck sizing. I neck size 3 or 4 loadings then full length size with my varmint loads. For big game loads I prefer new brass (neck sized) or full length resizing fired brass, I set the full length sizing die to bump the case shoulders .002-.003" for chambering reliabilty.

I have heard of a situation where a fella left his rifle out in his truck overnite in extremely cold temps. He stored his neck sized ammo inside his warm house and the next morning he could not chamber any of his ammo due to the difference in tolerances. Never had it happen to me with my varmint rifles but who knows I could be next....................

MtnHtr

I certainly wouldn't partial neck size the 30-378,as it is a good way to induce setback,as you know. Sizing the full length of the neck,with adequate constriction,will negate setback,assuming sound brass.

With an FL die,one can partially neck size,size the entire neck or bump the shoulders,while sizing all of the neck.

If you are not on your game,neck sized fodder can bite one in the ass,at inopportune times. I don't Hunt virgin hulls,as I believe it to be bad JuJu,but that is a hangup of mine. I also don't Hunt brass that hasn't been run through the rifle it's for,prior to the bullet seating operation and that as just another function confirmation check.

Work hardened brass,is another way to taste setback. Once elasticity is compromised,setback is a given in the boomers,especially if one favors coated projectiles.

Good brass is important,for lotsa reasons................

I do. You can do it for about five loadings, I size the full neck, Redding S die with .332 bushing. My seated diameter is .333 This after 70% cleanup of the neck. My neck die does resize the sides of the case as well. After five a shoulder bump is needed (if the pockets are still good). I can't think of any good reason in partially neck sizing with these slow burning powders. I can't comment on whether the recoil moves the bullets as I have only had them in the magazine once during a bear hunt and never fired a shot.
Good Luck,
Shummy