I watched a bit on Brandon Lee’s death like a decade ago (so may get some of it wrong) but that one went down like this….
They loaded the gun with empty bullets (casing and bullet tip/no gun powder) and fired it off at the camera so looking down the barrel of the gun on a close up, you’d see the bullet tips in the cylinder.
Cuz blanks don’t have bullets “tips” just the casing (I’m Canadian… I don’t know guns heh)
So one of those gunpowder empty bullets had some residue, and when fired the pin ignited a “bit” and the bullet tip came out and went into the barrel… no one noticed
Then they loaded the gun with blanks for the wide shot… gun powder shells with no bullet tips…. BUT A BULLET WAS NOW IN THE BARREL.
So on the wide shot, the actor fired the gun at Brandon, and that was it….
It’s been forever since i saw the rundown, but I believe that’s the reason.
Really the amount of guns fired and bullets used in movies, it’s surprising it doesn’t happen more often.