Gun show reloads strike again. Fortunately, the gun was intact.
This is a casing from a 9mm reload, fired from a Glock 19. It’s a standard-pressure, 115gr FMJ sold in bulk at local gun shows. What you’re looking at is a case-head failure. This can break a gun really quick.
It can also lead to severe injury. Saving a few bucks isn’t worth taking such risks.