Piercing primers

Ol Rob

Sergeant
Full Member
Minuteman
Mar 16, 2008
460
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58
Tifton, Ga.
I am at the end of my rope. I am working up a load for my custom 223. Surgeon action, 1:7 broughton barrel. I am getting random pierced primers. I say random because I have continued to work DOWN in powder to reduce pressure. I am at 24.1 gr of Varget behind 80gr SMK's. Remington brass with CCI 400 primers. I killed my second trigger yesterday. This is getting expensive. No other pressure signs.
Suggestions? At 24.1 I am not getting the velocity I need to go 1K yards accuratly. Could it be the brass? Shallow primer pockets?
Rob
 
Re: Piercing primers

Are you headspaced correctly? I am aware the difference between go and no-go is very small with 223rem, I had this issue when I was fireforming 6.5x47L and brass was being blown fwd .007. A hard jam solved the problem. You could have a pin protrusion problem but that would be doubtful with a custom action.
 
Re: Piercing primers

Ol Rob,

Too close to the lands. Necks too thick. Unsorted bullets. Inconsistent case weights. Flash holes too big. Bad tip on FP. Unbushed FP.

I'd sort the bullets first, then weigh cases. I've had SMKs vary by 0.020" in the same box of 500. Remington brass has had up to 5.0 grains of case weight variation from lightest to heaviest.

HTH,
DocB
 
Re: Piercing primers

Rob,
Check your firing pin tip. I have found with the AR 15 ( I know your using a bolt rifle) that sometimes a light stoning of the tip would stop pierced primers. My overall guess is switch primers. I have heard many complaints from other people about having piercing problems with the CCI 400. Try the CCI 450, Wolf SRM, CCI BR4, or Rem 7 1/2 if you have any. Your load does not seem too hot, but a lot of things can alter chamber pressure.
 
Re: Piercing primers

I'm using 75gr Hornady's with 23gr of RL15 and it's on the warm side. 24gr was HOT in my rifle, and I'm using a lighter bullet. I realize these are different powders but they have a very similar burn rate. Sounds like you might be a little on the hot side to me.
 
Re: Piercing primers

I'm running 24.5 gr. of Varget behind a 75 gr HPBT in my ar with no signs of pressure. I had a problem with my .223 Ackley in my savage bolt rifle that would pierce cci-400 primers, I started using Wolf Magnum primers and all my problems went away. The Wolf primers didn't effect the accuracy either.
 
Re: Piercing primers

Buy another batch of primers. I got a bad batch years ago and took me quite a while to figure out that they were bad. If you still have problems with the new batch then at least you have ruled out the primers.

Good luck

Jerry
 
Re: Piercing primers

I have sent the bolt off to have the firing pin hole bushed. I will try different primers, I have a couple thousand federal match.
Thanks for all the suggestions.
Rob