Originally Posted by s&wchad

The issue your having is referred to “cylinder jumping lug”. That problem happens when fired cases stick in the cylinder and and you apply a lot of force on the ejector rod, without supporting the cylinder. When S&W made the change from the pressed in steel frame lug to the integral frame lug, they didn’t make the ledge that limits rearward movement of the cylinder tall enough. That’s my opinion, anyway. It’s worse on alloy frame guns, where the harder steel or titanium cylinder contacts the aluminum alloy lug..