I certainly cant tell what caused the barrel to leave the frame's company in such a way, but I would certainly say the gun blew up for sure. While not the same as a cylinder blowing up through the topstrap, it certainly is bad enough and it sounds like the more I hear of it there might be something wrong with those lightweight J frames. Granted I own a 649 but I have been a bit skeptical of wanting a new J-frame, even though I know it could have been an off day at the factory, who knows the guy screwing in the barrel could have had a hangover, not enough coffee whatever. But I'm glad to see you are ok and the factory certainly owes you an answer.

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Vaya con Dios