Shot Mitigation, perfectly normal in apex TSS shells I think.
The Federal, Browning, Foxtrot loads, Didn't rattle. I was told they aren't supposed to rattle. But I haven't seen an apex tss in any gauge not rattle. So who knows. Rattling can move powder, and cause inconsistent ignition whether it being too hot or too light. But maybe someone with knowledge on loading solid safe shells can reply. I know Apex has had recalls, with stuff splitting barrels, chambers being trashed, cutting corners making dynamite.