Factual error: When the bad guys are looking through walls with the rail gun's scope the light on the gun shines through the wall, but in real life it doesn't do that unless you are looking through a window. (00:27:15)
Continuity mistake: When Arnold blasts out of the warehouse with 2 EM Guns, a man is firing at him, standing right next to a surveillance van. Arnold fires back and blows the whole van up but the man is gone. (01:38:20)
Factual error: When the Feds are going to the log cabin, while they are outside, gearing up, Arnold casually attaches a silencer, and pulls back the slide of his pistol, but the slide stays in the rearward position, a condition which should only occur when an empty magazine is in the weapon. Arnold notices and tries to push it forward, this doesn't work so Arnold hides it with his hand for the remainder of the scene. (00:42:50)
Continuity mistake: Arnold is handed an upside down photograph of his friend's witness. As he views it the photograph is correctly oriented without being turned around. (00:41:05)
Continuity mistake: It's astonishing that Arnold still has a gun after he jumps out of the plane since he didn't holster it before he jumped. Still he pulls it out of his holster before he shoots the plane and during the shootout in the zoo. It's also pretty strange that this weapon, a Desert Eagle .357, fits into the holster, since Arnie's first pistol (the one the young Marshal was shot with) is much smaller. Another fascinating thing about the gun is the fact it has a maximum capacity of nine bullets plus one in the chamber but Arnie fires about 15 or 16 times. (00:56:20)
Other mistake: When Arnold and Vanessa are in the dead guy's office running the CD, Arnold pulls up the shipping date for the arms deal. The screen shows the date to be "TODAY" and Arnold says "Midnight Tonight." Midnight would be 12:00AM, so the screen ought to read 12:00AM tomorrow morning, not today. (01:22:00)
Factual error: After removing the first parachute, Arnold uses the emergency one. However, when he deploys it, he is only a few hundred feet off of the ground. At this height, the parachute would do nothing except possibly snap Arnold's spine. (00:57:10)
Other mistake: When Arnold lands on the car in the junk yard, you can see the side windows of the car exploding outward moments before impact. (00:57:10)
Plot hole: There's absolutely no reason why Kruger had to page Lee from the plane after he'd been drugged. The bad guys had no idea where Lee was until he did that and they traced the phone call. Not only did Kruger give away Lee's location, but he also gave away the only thing keeping the bad guys from killing him.
Other mistake: In beginning of the zoo scene, Cullen shoots J. Scar in the leg and he collapses in pain. For the rest of the scene, he pursues Cullen and fights as if nothing was wrong with his leg.
Factual error: In the train wreck scene at the end of the film, we hear the railroad warning bell clanging, the train horn blaring, James Caan and friends screaming, the fiery roar of the impact, and the rumble of the train plowing through the wreckage. In reality, all of these sound effects would have been drowned out for the duration of the scene by the ear-splitting, squealing screech of powerful railroad brakes that the engineer would have applied long before an unavoidable impact. Omitting the sound of railroad brakes is still a common factual error in modern train-collision sequences.
Continuity mistake: After Cullen has been picked up by the FBI agents they are sitting by a table where Cullen is explained there would be risks. There is a coffee pot on the table and a white paper cup on its right side. When it cuts the paper cup has moved to the other side of the pot. (00:20:25)
Revealing mistake: When Cullen is in her office wearing the hidden camera disguised as an amulet, we see her from the hidden camera point of view while she is looking in the mirror. You can see she is moving a bit however the view from the hidden camera is perfectly still. It should wobble a bit as well, not standing still. (00:13:20)
Continuity mistake: When Lee sits down to copy the files from Cyrex, the wide shot shows the clock as 10:25, a few seconds later Lee checks her watch then looks at the clock on the wall which then changes to 10:26 but then after she is done making the second copy the clock on the wall is back to 10:25 again. (00:16:25)
Audio problem: At the beginning of the film when Kruger rescues the mafia guy and his wife they hurriedly get in the car. Kruger somehow manages to pull down the gear shift immediately before cranking the car up. Listen closely you can hear the ignition starting after he's pulled the gear down.