Why would he point the gun at her in the first place, even so she had no part in the movie and then pulled the trigger twice was he just showing off and fooling around? Even so in my opinion he is just an ignorant, hypocritical, blow hard actor, like most of them are there is no reason why he couldn’t have looked and checked what this six shooter was loaded with.
In case of a revolver quite easy to do and when the cartridges looked suspiciously like the real thing he should have said “Wait a minute and lets find out” Well maybe I am asking too much. But when it comes to guns, the first mistake also could easily be the last one. And by the way I have nothing against guns and have been shooting and re-loading for the better parts of forty years.
open the chamber, empty the rounds
load blanks or nothing
hand to moron actor
stupid simple
Reported he was angry with the director and/or cinematographer who wanted another take on the scene they had just filmed. He was told the gun he was handed was "cold" (no live fire) so being pissed, pointed the gun at them and said "how about I shoot you" and fired. Only one shot, went through and killed the woman, and hit the director in the shoulder.
Whether he's charged and prosecuted in liberal Santa Fe County for his action is questionable.