Re: Primer cup burn through
It's been happening to me, too on my Small rifle primers, Remington's, CCI BR 4, and CCI 400's as well.
It's not good, it will pit the face of your bolt, and or firing pin. Then they have to be repaired/and or replaced. Bad, worn or sharp firing pins can cause this. My firing pins are all new, and mirror smooth/round.
There are only two seasons: Hunting season, and Getting Ready for Hunting season. -DAD