Originally Posted by ken snyder
Brief check list: too much powder, Moly bullets on a cleanly stripped barrel. gas check bullets and a tight neck or donuts. Holes in primers with a good pin are from too large of a firing pin hole. Blown out of pocket primers are from over worked (too much pressure) brass or improper pocket cleaning that enlarges the pocket. The ABSOLUTE BEST diagnosis tool will be to shoot factory rounds and I'll bet the problem goes away, if it doesnt, you need to find the problem.
The problem is definitely not there with factory ammo, I have shot winchester, and hornady factory ammo and the primers appear just fine. As far as my cleaning method, and waiting till 100 rounds to do it; guys, this is a prairie dog rig, and for personal preferances, I don't want to stop after every 20 shots to clean the gun. I know it will make for better accuracy, and the barrel will last longer...but when I'm prairie dog hunting I want to shoot accurate, dependable hand loads, for a whole weekend. If I'm doing any cleaning, it will be done at the hotel, after a full day of shooting. I know that this will not be a bench rest competition gun, but I know for a fact I have done it this way with 4 other rifles and they all consistenly shoot sub moa. I have never had this kind of problem before.
Ken, what you said about the brass being over worked makes sense. I just read a handloader magazine article about neck sizing and then form firing new brass. It said that many handloaders like myself, fall into the trap of believing that major brass manufactures don't know what there doing, so to fix all of their mistakes we should full length size our new brass. (Yes I did this, maybe the brass is overworked). Aside from going and buying new brass and starting over, is there any way to tell if the brass is overworked?