Neck Tension Question

jsthntn247

Gunny Sergeant
Full Member
Minuteman
Feb 25, 2009
1,208
144
Mississippi
I just annealed my Win 308 brass after 3 firings. My bullets are seated a hair long to feed through my hinged floorplate magazine and the tip of the bullet hits the feed ramp. I cycled all the ammo throough the gun and 3 out of the 20 bullets had pushed back .025 further back into the case. I pulled on the tip of the bullet and was able to extract the bullet by hand. I ran them back through the neck sizer, re-loaded them, and was still able to pull the bullets out. The brass was annealed 6 seconds and shows no sign of being over-annealed, not blue or chared marks anywhere, they look just like Lapua brass that's new in the box. I am going to seat them .025 off the lands from now on so they don't hit the feed ramp, but did I over or under anneal these 3 cases?
 
Re: Neck Tension Question

I don't believe you "over annealed" them. Sounds more like a die/process problem if you can move bullets with your fingers.

Have you measured the inside neck diameter after sizing? It should measure .002" .003" less than the bullet diameter.

What dies are you using?
 
Re: Neck Tension Question

I resized all brass with a lee collet die. I'm only having a problem with a few out of the whole batch. If it is a neck thickness variance issue, are the problem necks thinner or thicker?