LT.Diver said:
almost as though the producers feel that weapon related authenticity is completely unnecessary.
I think that's it right there. And I'll take it a step further: I think a lot of the bad gun stuff is done on purpose.
For many people, all they know about guns is from what they see in TV and movies. So if producers and directors showed guns and gun handling with 100% realism, many people would probably think it was LESS realistic. For example; if a movie showed what a silencer really sounded like (especially a rifle silencer), many people might think it was unrealistic. Or if they showed an actor using a thumbs-forward grip (in my experience, a thumbs-forward grip looks odd to people not familiar with it). Or if they showed how loud guns are (especially when fired indoors). Or if they showed someone getting shot with a shotgun and NOT flying backwards. Or if they showed someone drawing a gun but it didn't make a cocking sound. The list goes on and on.
And the worst offender is the constant finger-on-the-trigger. I'm convinced that producers and directors specifically tell actors to put their finger on the trigger (maybe to look more menacing or something). If you notice, in almost every movie poster and video game cover where the character is holding a gun, they have their finger on the trigger. I think it's too common to just be bad gun handling; after all, many actors get great real-life gun training for certain roles. For example, Tom Cruise got a heck of a lot of training from a former SAS operator for his role in Collateral. But here's a poster for a movie he filmed after that:
I'm convinced they told him to put his finger on the trigger for that picture, because he must know better than to do it on his own.
Also, I remember seeing a Time magazine cover of three soldiers in full combat gear with their fingers on the triggers of their rifles. But that safety rule is greatly emphasized in the military, and especially in the Army and Marine Corps. I'm convinced that the photographer who took that picture instructed the soldiers to put their fingers on their triggers.