I think the pistol being used and the brand of primers has a lot to do with it. I tried some S&B small rifle primers and couldn't get them to light. I had cartridges with 3 dents on the primer cup and they wouldn't go off. I read the description on the box (in Czech, thanks to the Army, I could read it
) and it said primers for Kalashnikov, They worked great in my AR, I figured they were about equal to CCI #41 primers. I've not had problem with CCI #400 SRP or Winchester small rifle. I sold the 10K S&B small rifle primers to a friend who does 3 gun. Everyone was happy