Pardon my ignorance, but I apparently know nothing of the movie industry. I guess my impression has always been that "prop" guns on sets are not capable of firing actual bullets. I thought they were akin to something like a toy gun, like you'd buy your son, but that looks more convincing on the outside. A toy, capable of making a little flash at the barrel, if desired.
Reading through this discussion, it sounds like gun used on tv/movie sets are real guns that get loaded with dummy rounds? If so, that is.....just.....I don't even know what to say about that.
Granted, I have no experience with dummy rounds. I have no idea if they're supposed to be easy to identify or if I should be able to easily tell if the bullets are real or dummies. I've never used them.
That still is just asking for trouble. If I--an owner of a few guns and while pretty limited in knowledge and experience, not completely unfamiliar with firearms--don't know anything about live rounds vs. dummies, I would trust a bunch of anti-gun Hollywood yahoos to know anything about it. Production companies would know that, you'd think, and would not assume anyone on set knows anything, therefore you use fake toy guns or at least have a prop master who is an expert in firearms, and to boot NO live ammunition is ever allowed anywhere near a set.
I still can't wrap my head around using real guns for filming. I guess there's a reason for it, but it's not like it'd be hard to have convincing fake guns that are not capable of firing squat.