Realism hole (spoiler?)
After Emmett shoots up the can, he gets ambushed. But anyone who lived by the gun the way he had, would have reloaded the second he was caught, or while running for the rifle. His arms were still free when lassoed, yet he didn't try to reload. All he needed was a couple of bullets loaded to do what he had to do. It isn't that hard and doesn't take that long to drop the empties and stick in a couple of rounds.
Getting caught and doing nothing but running doesn't equate with the opening of the movie.