Factual error: During the final battle, Gordo the tank driver calls out, "Panzerfaust, four o'clock!", as he looks through his periscope. He could not have seen any targets at four o'clock, as the driver's periscope could barely rotate towards the eleven and one o'clock positions, close to the left and right front corners of the tank's hull. The four o'clock position would be near the right rear of the tank.
Factual error: Chris Kyle did not make Chief after his first deployment. He made Chief during his fourth deployment.
Factual error: In the third scene, where the woman is being dragged away, you can see the incisions from breast enlargement surgery at the bottom of her breasts, hardly fitting the time period. (00:01:25)
Factual error: When the Germans come to the town a tank rolls through the picture. The first shot shows the tracks, then the whole tank is shown and one can see the tracks again. The turret suggests a Panzer III (which would be accurate for the time). It appears however that the tank is a modified Russian T34 or T55 or something as the road wheels are too big for a Panzer III. (00:13:00)
Factual error: The film is based during the Battle of the Bulge which took place from December 16th 1944 to January 25th 1945. However throughout the entire film the area appears to be mid-summer. No snow in sight. (00:07:50)
Factual error: During the Hungnam evacuation scene in December 1950, a U.S. Army Captain is using a radio handset. The model he uses is the H-250, which was introduced in 1987, over 30 years after the Korean War.
Factual error: The three panzers that ambushed the Hellcats are supposed to be Mk. III's with the 50mm gun, but they only had 5 bogie wheels, instead of 6, and no driver or radio operator's hatches.