I've spend some time researching this one, the actors are just "dummys" on set - they are handed a firearm and told to do xyz. They aren't to check it or manipulate in anyway beyond what the armorer has told them to do - this is SOP in that industry. So here, how would he have known what was a blank and what was a live round or even be allowed to check? At some point, there will be firearms pointed at other people on a set, how else will you get all the various shot angles etc.? That's why there is no live ammo allowed and the guns are ofter neutered so they couldn't fire a live round if you wanted to. I never understood why he was ever to blame here, the armorer has the blame on this one for ever allowing live ammo on set which she did and is negligent of. If he did something he wasn't supposed to/against the instructions, sure but that's not how I understand/have read the accounts of what happened. Brandon Lee was killed during filming of The Crow in the early '90s when a firearm was discharged that had a projectile of some sort/part of a blank in the chamber. It is rare but has happened. Nobody here would, as an actor, go against any rules/protocols that were setup on set w/r to firearms...if you were handed a gun and told to point it at so and so as part of the scene, you would do it and assume (you'd have to!) that it was safe, why wouldn't you? We all understand the 4 universal firearms safety rules, but there are situations, like a movie set where they will not be upheld b/c other controls have been put in place to prevent issues/circumvent those rules. I believe they do their best to never have to point guns at anyone on set with angles etc. but at some point, it's going to happen and be part of the job hence the protocols in-place and the job of the movie's armorer.