Looking for examples in doubles, as a result of steel shot. (Or even lead shot, for that matter.) What loads, through what guns, have caused problems that you've observed? On the other side of the coin, what loads have worked out for you through what guns? Wondering here in particular about older American guns, plus European guns that are CIP standard rather than superior or magnum proof.

When referring to chokes through which you've shot steel and which have (or have not) resulted in bulges, if possible please specify the constriction if you know it (rather than just mod, full, etc). Thanks!