Other mistake: While Ransom Stoddard and his wife are on the train back to Washington, the conductor tells them that the train will be able to maintain a speed of 25 mph throughout the journey. The film is set around 1900, by which time trains were regularly topping 65 mph, and the outside scenery is moving faster than it would for something traveling at 25 mph.
Other mistake: The villain's plan is to impersonate along with his large crew a platoon of the Mexican army. He already captured the soldiers and has them incapacitated, all he needs to do is take their uniforms. Instead of doing so, though, he mows down the whole lot with a heavy machinegun. When it's time to put on the show, everyone wears nice and tidy white uniforms.
Other mistake: Jed has eight rounds on him/in his pistol. He tells Chad to go to his saddlebag to get another round of ammo and keep it in his pocket. Jed tells Chad "Let's play catch the bullet" since Chad (not his marshal dad Britt) is the only MacMasters there. Jed fires six rounds before Britt shows up on top of the hill, then two more (eight rounds). Jed shoots a ninth and tenth round before he tells Chad, "Get that ammo." Chad is never shown giving Jed the ammo from his pocket, but Jed keeps shooting. (01:13:42 - 01:17:46)
Other mistake: The steer horn that penetrates Forrest Tucker near the end of the movie is at right angles to the rest of the steer horn.
Other mistake: When Regret, Jake, Pilar and her father are escaping from the Comanchero village, there's a close up of Jake (Wayne) in the back of the wagon shooting a rifle. The scene shows him shooting left-handed. It's a reverse print. Look at his "right" hand in the scene. He has a ring on his "right" hand ring finger. A few moments later, setting the wagon canvas afire trailing out the back of the wagon and shooting right handed, the ring is on his left hand as it is in the rest of the movie.
Other mistake: A brief section of the film was flipped. One building has a sign saying "FIREARMS" and the lettering is in reverse.
Other mistake: In the beginning of the film when the stage coach is approaching Minnie's haberdashery, a well-worn horse path when approaching the haberdashery but it's been snowing a long time, and there is not a lot of traffic going to the haberdashery so this path should not be so worn.
Other mistake: When Bob Hope is singing Buttons and Bows with accordion, to a sleepy Jane Russell, no-one is driving the horses.
Other mistake: When the old man was resuscitating the unconscious boy he kept his arm sticking up in the air. His arm should have been besides his body, limp and unmoving.
Other mistake: Brian Keith sneaks into an Indian encampment at night while they are sleeping. In order to stampede their horses, he rapidly fires the one and only six-shooter revolver he has into the air...eight times.
Other mistake: When Paris gets to prison he has a wad of money on him. Before he got that far the court would have taken the money away and given it back to the guy he stole it from.
Other mistake: The old man is plowing the field in front of Belle's old residence. The little girl picks up the doll. A second before the cut, the girl lifts her eyes from the doll and does not look at her pops, or around; she looks right at the fourth wall and smiles, waiting for her cue. (00:01:50)