I nearly stacked on in my 300 BLK. My sis was shooting it suppressed, and apparently there was a squib. I just happened to be watching and noticed that it sounded TOO quiet. The action didn’t cycle and she yanked the charging handle to load another round.
I caught her right before she pulled the trigger. She is new, and so didn’t think anything about it when no dirt flew up down range.
I don’t expect there would have been an injury, but it would have ruined a barrel for sure!