cratered Primers

[Hanic]

My new 6mm br build with a savage LRPV with Pac Nor Barrel is cratering primers alot. My search on the subject turns up a statement by the moderator that savage and rem often need a firing pin bushing. Can I measure my pin and bolt hole to see where my gun is re: acceptable limits. Anyone have specs for these measurements. I started with 30 gr varget with 87 gr Horn Amax. I dropped to 29 gr after seeing the cratering. The reduction really didn't effect the cratering. I'm using CCI 400 with new Lapua brass. The cases expanded by zero to 0.001" just above the web. The accuracy was modest at 3/4" for 3 shot groups at 100 yds. Anyone have any other input on this? Thanks for any help offered. Hank

 

[NorCalMikie]

Hank: One thing that Fred at Sharp Shooter Suppy said was "If you want the firing pin bushed, I'll do it for you but,I don't think it's needed"! If it was a Remington I could see doing that modification. HTH. Mike.

 

[Rust]

Primer cratering can be caused by headspace issues too. I've had some out of the box new brass that was a bit short to the shoulder and it caused a variety of primer indications with milder loads. One way around it is to create a "false shoulder" in the neck, the technique of which is described in the 6mm br technical articles. Pretty much the same technique I have used to form Ackley Improved brass.

 

[tripcrow]

Hanic, the LRPV I had and the ones I’ve seen at the range along with near every one of the past dozen or so Savage Varmint rifles I’ve had had ugly primer hits. If yours is like most those hits are also all over the primer, instead of being centered. Take a look at a box full of fired cases and you’ll see what I mean. Indexing the cases as you load will likely show you that the pin is hitting at different spots. I wonder if Savage may be a little generous with the size of the firing pin hole in the bolt head to compensate for the way the head floats??

If you have a good barrel with a nice centered chamber you don’t want a firing pin that’s pushing the case every which way. I’d look into getting the thing bushed and maybe trued some if needed. Check with forum member RustyStud as he works with Savages regular. Or there’s always SharpShooter Supply.