pressure signs in my 223

[jec]

Any input will help here. I have a savage target action chambered in 223 with a shilen 8 twist barrel. I am shooting fireformed brass necksized only with the following:
24.2 grn varget
80 grn berger vld
cci 400 primers
I am shooting the above .012 off the lands and have done a ladder test to find the charge rate that produced the least amount of verticle. the loads shoot great at all yardages, but, and here is the problem when the temp. goes up the primers are cratering or piercing. This is only a problem in the late morning when the temp gets up to about 85 degrees. If I decrease my load then I will get verticle stringing out of my groups. The only thing I havent tried is to run a ladder test further off the lands to see if this will solve my pressure issues. I thank anyone for their help.

 

[2506]

Try you some Wolf small rifle mag. primers. They have thicker cups and the lowest SD I have ever seen.

 

[jec]

Thanks for the info. Going to the range today to test for pressure signs. Loading remington 7 1/2 primers will post report for anyone else with same problem.

 

[Winchester69]

Take a look at your firing pin. If it's not damaged, it may need to be bushed.
.

 

[jec]

Sorry it has taken so long to post range results, but I finally made it to the range and the 7 1/2 rem primers show now pressure signs. thank you for the help.