When Cavanaugh is stalking Ruger through the warehouse, he inserts a fresh magazine into his pistol after emptying it at Ruger, but he has to rack the slide to get a shell into the chamber. He should not have had to rack the slide, it should have been locked back after the last shell was fired from the now-empty magazine. In fact, he is never shown ejecting the magazine after emptying it.
When Ruger shoots from behind the forklift in the warehouse, her gun is aimed at an upward angle, yet the bullets are shown striking at a level angle.
When Ruger electrocutes the guy in the hot tub with the television, the TV is clearly not plugged in nor does it even have a power cord.