Light primer strike.

[floydthecat]

Sure, maybe a punk spring. If you changed it with GI it would probably be magic. We'll never know now.

Maybe OP will provide the outcome. Could be a number of things and seemingly not ammo. OP, being a reloader, could have built some longer rounds to see if head space is at issue.
I am not convinced these commercials ever pay much attention to it most of the time.