I'm trying constantly to put my mind into this deal as an actor and not a gun guy. What I've come up with is that the rules of firearms don't apply to these folks. Explanation. They are not gun people and may or may not know the rules of safety. Even if they have a basic knowledge of guns they may blow off the safety rules because they are supposed to point guns at people they want to pretend to kill. Possibly the overriding safety fact they should be totally confident in is that there is absolutely no reason for live ammo to ever be anywhere near a movie set. Period!
My guess would be that with really strict people in charge of firearms on a set, there would be safety instructions for each and every person that might even have any reason to touch one of the firearms. And, if said training didn't teach every person how to check the firearm, then the armorer would be negligent.
Personally, I imagine that Baldwin has been in more than one movie where he is handling firearms. I know for a fact that he "used" a 1911 in "The Hunt for Red October."