I had a blow out the back, again. Both times on Winchester once fired brass. 1911. 4000rds - 2 failures so far - one last year one this year. 45ACP - 4.2gr Clays w/ Rainier 200gr flat nose electroplated bullet. Dillon 650 w/ overcharge warning system. The first one blew out the bottom of the magazine, this second one, the bottom of the magazine held tight (CMC powermag vs. welded floor plate mag) forcing the gas and powder out the back from around the grip safety. I don't cruise the reloading forums much anymore. Is it just me? Wanna kill these ads? We can help!