I recently was given a bunch of range pickup .45 ACP brass for almost nothing that had been tumbled. As I was inspecting the cases, I found several cases (all RWS so I'm assuming loaded by the same person) possibly appearing to be reloads with cracks around the case head as shown in the pics. What would cause this sort of stress? Overpressure load fired from unsupported chamber? I know I've discarded at least 10 of these, but at least some of these have some pretty deep primer indents as shown.