I would bet its the ammo. That expansion near the rim doesn't look good. I wouldn't shoot anymore of it. Some of the reviews I read said shoot 410 shotshells designed for revolvers. Never heard of 410 shotshell designed for revolvers before. I would go back to a previous shell that shot OK.I’ve been shooting 410 shells in my governor every summer for almost 6 years and never had any problems. I think it’s the low brass.