I forget the name of the movie, it was on AMC recently I think. But it had a bunch of guys rapid firing bolt action rifles -- without working the bolt. And it was all on screen, not shifting perspective, so I couldn't dismiss it as the bolts being worked off screen.
Or when Glocks turn into Berettas. I mean, first of all, how hard is it to get the actor to pick up the right prop when doing different takes -- don't they have people paid to do just that? Second, if you can't get the buffoon to pick up the same prop, at least pick something that remotely looks like what you had before.
Re: Sons of Anarchy -- I saw that too, but thought I was seeing things, I'm not real familiar with balisongs or switchblades.