Other mistake: A shootout occurs in a hotel, where a shotgun blast apparently opens the money box. None of the perpetrators fired into the room.
Other mistake: Captain Stanley takes the lid off a small bottle on his right and puts the lid on the desk. He pours a drink and the lid miraculously appears in his left hand. He then screws it on the bottle. Screw top bottles weren't around till 1920. (00:54:50)
Other mistake: Before the opening scene, where there is a paragraph setting up the history of the musical, in the third line there is a spelling error: "it's" should be "its" since it is a possessive pronoun and not a contraction.
Other mistake: The opening credits misspell the name of production supervisor Peter Sczygiol ('Sceygiol') and firearms technician Gino Vagniluca ('Vigniluca').
Other mistake: At the beginning, when Rosie strips down to bathe in the lake, only her skirt comes off, revealing her bare bottom. But not her blouse.
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: Handsome and Charming head out of Snakes End (followed by the newlyweds) and begin their long journey. It then cuts to Cactus Jack before he begins the journey, and at the start of this shot as he places Whiskey's bit, we can see the signpost with three wooden arrow signs and the hillside behind him. This is the same location where Cactus Jack lays trap number seven, named "the tunnel in the hillside," on the next day during the journey; noticeable when Handsome and Charming arrive. (00:28:35 - 00:54:45)
Other mistake: A brief section of the film was flipped. One building has a sign saying "FIREARMS" and the lettering is in reverse.