What are Dimpled Primers?

[Ishallbie O'Cullkillin]

Got home from load testing and noticed a small raised bump in the center of the primer strikes. What causes that? The rifle is stashed back at the bat cave, but I can only imagine that my firing pin must need to be replaced. Incidently, I Was getting MOA with a Bushy carbine & 23.7gr AA2230 @ 2750fps.

 

[our gang]

Re: What are Dimpled Primers?

All it means is you have some flowback into the firing pin hole:

Load too hot
Pin hole to big
Pin diameter too small
Weak hammer spring
Too light hammer
Soft primers

Does it do it with mil-spec ammo?

 

[Ishallbie O'Cullkillin]

Re: What are Dimpled Primers?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Mr. Humble</div><div class="ubbcode-body">All it means is you have some flowback into the firing pin hole:

Load too hot
Pin hole to big
Pin diameter too small
Weak hammer spring
Too light hammer
Soft primers

Does it do it with mil-spec ammo? </div></div> Yes, mil-spec L.C. xm193, and some 69gr HPBT handloads , the hottest of which were 24.7gr Tac, 24gr AA2230, 26gr Varget. Fed, WSR, CCI primers.

 

[our gang]

Re: What are Dimpled Primers?

If everything is "stock", I'd be checking the firing pin size relative to the firing pin hole in the bolt.