Couple of points I missed and probobly not relevant here , is that on occasion you get batch of cartridges that have harder than normal primers .
Production being such that when this occurs you may have a whole load of them , but if you have tried different brands then this probobly not the case .
I have also come across and accepted the strange fact that some guns do not like some cartridges .
Amen to that. It doesn't just mean problems occur when ammo is being fired. There are also the nightmares of problems during ejection attempts, also.
