Blooper

In the first Expendables movie, Lee Christmas has his Expendable tattoo on his right forearm. In this movie it's on his left forearm.

After being rescued from the prison transport, Doc tells the other Expendables that Barney still hangs up the dog tags for deceased members in the plane as a memorial. In the second movie, the original plane crashes and gets buried in the mine. Those original dog tags would have been on that plane and not the new one. It is possible, though, that Barney would have made new ones to keep the memory of the fallen alive when he was outfitting the new plane.

During the final action scenes when the biker rides up the plane tail, he hangs on to a metal rod with one hand and fires at the enemies with the other hand (his helmet fully on) swings and when he lands in the next shot, he has no helmet on.

At the start of the film Gunner, Christmas and Toll climb onto a helicopter. When the helicopter is in the air, they have switched sides. (i.e. Gunner is on the left side of the chopper on the ground but the right side in the air)

(at arouns 1h 19 mins) When the plane is taxiing before leaving for the rescue mission and pulls up in front of Barney's old team, both propellers are standing still, despite rotating in the shots before and after.

Barney's plane is Russian AN-26 which is a turboprop, but the sound it makes is of piston aircraft. Also, AN-26 can not fly from New Orleans, LA to Bucharest, Romania without refueling.

The helicopter of Conrad Stonebanks bears the roundels of the Bulgarian Air Force and not of the Somali Air Force. Filming was done in Bulgaria.

When Bonaparte is first showing Thorn to Barney, Thorn is rock climbing, He slips, falls, and deploys a bright blue parachute. When the scene cuts to Thorn landing someplace behind Barney and Bonaparte, the parachute is red.

Correction: While Thorn's parachute is blue, his slider (rectangular piece of fabric where the parachute lines attach to the harness) is red. It is this red slider that is seen as Thorn is landing, the actual parachute is out-of-frame.

The team is arriving in Bucharest and jumps off the plane. In the next scene the team is in the center of Bucharest. There was no need to jump off the plane with parachutes, they could easily land and proceed to their mission.

Correction: They are on a black ops mission, landing at an airport or airstrip would risk encountering customs or law enforcement.

When Stonebanks shoots Caesar one of the bullets hits him in the top of his back, but when the team provide medical care to him the wound is now in the middle of his chest.

Correction: Stonebanks was firing at Caesar from a higher elevation, the bullet entered his back and passed through his abdomen at a downward angle, before exiting in the middle of his chest. They were applying pressure to the exit wound, with Caesar laying down that also put pressure on the entrance wound on his back.

The bomb that Stonebanks drops from the helicopter during the opening battle is a Mk82 Snake Eye, a high drag version of the Mk82 Bomb. These bombs are unguided. The fins that deploy when it is dropped are only used to slow the bomb down for high-speed, low-altitude deployment. They do not fly the bomb to its target. When dropped from stationary helicopter, it should have dropped straight down and missed the team entirely - instead of flying towards the team and landing on the truck.

When two of the Expendables walk across the glass roof of the art museum, an assault rifle is just lying there near the building edge, for no apparent reason.

Just before the 50 min mark, Lee Christmas throws a knife, after seeing where the knife ends up the camera pans back round which sees Lee walking away. The camera cuts back towards knife, then back to Lee, who is now standing in the position where he threw the knife from.

In the end credits the actors are shown with the weapons their characters are known for, like Jason Statham/Christmas's throwing knives, Dolph Lundgren/Gunner's Bowie knife and Arnold Schwarzenegger/Trench's AA-12 full auto shotguns. However Sylvester Stallone is shown with a SIG Sauer P228, which isn't either of Barny's signature handguns, i.e. his dual custom Kimber Gold Combat II .45 ACP's and his custom Colt Single Action Army .45 Long Colt.

When Barney is hanging from the helicopter near the end, the view is from inside the helicopter with the skid below. Barney should be hanging out of site below that, yet is hanging from a point away from above the door on an angle that would only be possible if the rope was attached to an outrigger arm at least 20ft away to the side of the helicopter. The winch used would be barely a few feet clear of the door and most likely visible from this point of view.

During the assault on the waterfront Doc jumps onto the roof of a passing truck. There is an armed guard walking behind the truck a short distance back, walking in the same direction. The guard would have easily seen Doc's movement and raised the alarm.

When Barney Ross and Bonaparte go to the appointment with Galgo, a caption says they are in Arizona. When they leave the car the license plate is from Spain.

The Haval has European vehicle registration numbers 3052 CFS with the blue European colours on it.

The meet between Stonebanks and the buyer is supposedly set in Moscow, but the signs at the entrance are in Bulgarian.

Stonebanks tells Vata that X-rays damage the oils in artwork, and therefore customs doesn't scan them. X-rays are actually frequently used to examine paintings. This is the method by which changes made by the artist, rough sketches, or even completely other works, are discovered underneath.

There are several times where Barney, and other Expendables, are walking around with their fingers on the triggers of their firearms. One notable example is when Barney is talking to Galgo about his old team. After they finish their conversation, Barney goes from pointing his M4 at the ground, to pointing it up in the air. The entire time he is holding the rifle with his finger fully wrapped around the trigger, and putting pressure on it. This is something a military and combat veteran would never do, as it violates one of the major rules of gun safety: "keep your finger outside the trigger guard until you are preparing to fire and keep your finger off the trigger until you are ready to fire; never fully rely on the safety as, like all mechanical systems, they can fail".