Continuity mistake: When the villains get the last of the plutonium out of the cache, we see one villain shoot the chain suspending a concrete cap; causing it to fall and close the hole. A short time later, we see Maggie exclaim that the plutonium is gone. The cap could not have been lifted because all the miners were taken away, yet the cap is gone and we can see into the cache.
Continuity mistake: At the end, the number on the helicopter is 711. As it takes off it is 712. (01:26:30)
Continuity mistake: When the villain has the gun to Billy's head, in one shot it's touching his head, in the next he is about 1-2 feet away. (00:33:45)
Continuity mistake: In the opening chase with the seaplane the fuselage changes shape from being pointed at the tail end to being square to load the jet skies and as they crash through the exploding bridge to being pointed again.
Continuity mistake: In the scene when the bad guy drives through the front of the airport, he crashes into a pillar. The truck stops flush with the pillar. In the very next shot it is a foot or so away from the pillar.
Continuity mistake: When the door gets blown in the room where Arnold Schwarzenegger (with a bag over his head) was strapped to a chair, Arnold and the chair fall down. From the shot behind him, you can see his right hand gets freed. Moments later when they help him back up, both his hands are strapped again. (00:06:00)
Continuity mistake: At the beginning of the movie, Dolph Lundgren throws down the battering ram which has "Knock Knock" written on it. Shortly after one of their vehicles reaches the top of the ramp and one of the enemy jeeps falls off the roof Jet Li screams "Shut up, Gunner!" at Dolph Lundgren. Just before he screams, the "Knock Knock" battering ram is back in the retracted position. A few seconds later, it is facing the front again. (00:03:50)
Continuity mistake: When the men are being attacked after spending the night in the abandoned town, the horde of people attacking them are all in dark colors such as gray and black. If you watch carefully, you will notice one man in white attacking. This man is shot down and dies, but a few seconds later he is alive and attacking still.
Continuity mistake: At the beginning, when the Expendables and Trench are leaving the interrogation room, we see Jet Li along with his main weapon leaving with them, but in the next shot, he picks up his weapon and leaves the kitchen.
Continuity mistake: Just after Billy dies, Barney says "let's take care of him" and Toll Road puts his cap on. In the very next shot as they walk away Toll Road's cap has disappeared.
Continuity mistake: When the bad guy's convoy is coming towards them, the good guys shoot a hole in the front of the truck right under the windshield. Once the bad guys crash the truck, the bullet hole is gone.
Continuity mistake: In the bar Gunner writes down Einstein's theory on a napkin. He writes it near the top on the napkin, in the very next shot it is closer to the middle of the napkin and the hand writing changes.
Continuity mistake: When Church gives Barney the piece of paper, the way Barney holds it changes between shots. (00:22:10)
Continuity mistake: When Barney leaves the bar the number plate on his bike is on the left, in the next shot it's on the right. (00:19:10)
Continuity mistake: When Vilian puts his sunglasses down at the end, they move between shots. (01:20:30)
Continuity mistake: When Booker and Barney meet for the first time, Barney's necklace is either covered or uncovered depending on the shot. (00:56:00)
Continuity mistake: When Vilain has the gun to Billy's head he has it in his right hand. However when he is squeezing the trigger, it's his left finger. (00:36:00)
Suggested correction: It seems to me that it's still his right hand but the camera angle changed for the close up for a better reveal of the trigger pull. So in real life, the camera would have been to JCVD's right side during the scene, but then the camera switches to his left side for the close up. Watching it in real time, it can look like the camera just does a zoom in and now the hand has switched.
Continuity mistake: When the bloke has the knife to Christmas's neck, the position of the blade changes instantly. Note the end of the blade and his ear. (00:35:50)
Continuity mistake: Just after Jet Li jumps out of the hatch at the start, we see the other guy taking a drink from his hip flask and you can tell the hatch is still open by the wind blowing his hair. Camera shows the outside of the plane and the hatch is closed. (00:15:00)
Continuity mistake: At the start, the lead truck reverses with the coming soon plate right on the ground. In other shots, there is about a foot gap. (00:03:00)