I agree with John on every ruptured barrel it almost certainly caused by an obstruction. To see both barrels bulged and ruined like that was possibly caused by a 2 3/4 inch round loaded to CIP specs. I realize the extra length adds a little pressure but on an older gun that may have been honed and the bore cleaned up over its long life and service. Why risk it. That's why I don't use the stuff AEROSTAR and the HERTERS From Cabela's in any short chambered old guns except NIDs, Trap-guns and a nice Trojan I use for sporting clays. Its too easy to buy or reload pressure correct ammunition.