In the opening scene where Jim is knocked out and laying on the ground, his arm is over his head and tight against it. When the camera shows him again, there is a gap between his head and his arm, then in the next shot, his arm is back in the original position, tight against his head.
During the map room briefing, "Coronel Sandoval's" hands change positions on the podium several times.
After Jim wrestles the gun away from Sgt. Bender and sits on the bench, the collar on the left side of his shirt is messed up, but when the camera cuts away to Thornwald Wolfe and then back to Jim, the collar is back in place.
The holes the X2 will make in the Turtle are visible and taped over before the X2 is brought out.
One of Wolfe's men states that the guns came, "Right off the assembly line." While mass production was in occasional use (most often with weaponry) the term "assembly line" did not come into use until the twentieth century.
During the briefing, the pointer used by by Thorald Wolfe is a typical classroom pointer with a rubber tip. This type of classroom teaching aid did not come out until the late 1950s.
When Jim West is using the explosive putty on the door, he places putty both at the center of the door and at the top with a single strand of fuse going through both. This seems pointless because once the lit fuse reached the first explosive putty it would detonate and the fuse would then never reach the other putty.