Thread: Overpressure - yeah or nah?

Been working up a 73gn ELD-M load for my Savage 16 223.

Reviewing the cases after the range session I noticed some pretty extreme primer cratering, but no sticky bolt, flat primers, extractor marks or anything else that would indicate overpressure. Quickload thinks I'm still under SAAMI max pressure for my exact load and I'm about 0.5gn over hornady book max.

Question for the experts: is this really overpressure or just excessive firing pin clearance on the savage bolt?

I recall using CCI small rifle magnum primers a while back and never seeing this sort of thing - the ones I am using now are CCI std small rifle, maybe the magnum primers had a thicker cup?

I'm reluctant to change it because it's performing really well.

I am using 23.7gr AR2206H.

Looks like a firing pin issue to me

It could be excessive clearance but more likely to be a weakened mainspring which is being overcome by pressure during firing. It needs sorting as a punctured primer can cause bolt face problems as well as high pressure gas leak into the bolt, magazine, etc. The Savage 110 action does give good gas protection to the firer, but nothing is 100% at 60,000 psi!

Yes primer still has rounded edges so not overpressure, my guess is too much pin protrusion

Savage firing pin protrusion is easily adjustable with out having to resort to grinding anything

Definitely a low pressure load , and also maybe an over sized case as well ??? .
To check put a piece of cellotape on an unprimed sized case and see if you can close the bolt

Broken firing pin?

Yes, you could try CCI450s. They apparently have a thicker cup.
I've also had this in a Barnard where spring strength and tolerances around the pin surely preclude the previously mentioned causes. It appears to show up when the pockets are overly deep for the primers so add that to the list of possible causes.

For future reference. I found this article very helpful to put pressure symptoms into perspective.

https://www.primalrights.com/library...nding-pressure

Thanks for all the pointers team.