I had one last year. Bullet travelled about 1/2 inch up the barrel, I poked it back out with a cleaning rod. A couple of days later I had a hang fire from the same box of ammo. Hornady red tips believe it or not? Not had any other problems yet with hmr ammo. I understand that the Winchester HV varmint are supposed to be to a better standard but I haven't tried any yet. Got some of the Winchester supremes to use up first, then I'll give them a go.