Continuity mistake: Doc Riedenschneider calls on Cobby in a dark hallway with brick walls and a door in the end with a half-open transom. Through this door, in the adjacent room, there are several gangsters seated a table. They go down the hallway and enter this room. In the next scene they have entered and the seated gangsters are suddenly no longer there. Nor is there a transom over the door. The hallway viewed from this room has white walls now instead of brick.
Other mistake: A glass is dropped which had drink and one ice cube in it, however two ice cubes are picked up from the spillage.
Factual error: Between Earth and the Moon the crew of the spacecraft have an EVA in which they walk on the ship's metal hull with magnetic boots. At one point an astronaut inadvertently slips both boots off the hull and drifts off into space, helpless. There is a long shot of him drifting away in which his body spontaneously spins around 180 degrees and then stops rotating, which is all a violation of conserved angular momentum.
Revealing mistake: Having been deserted by their porters three white people and a native journey on. During their journey an antelope is shot by Allan Quartermain for food. The sound of the shot is dubbed in as there is no recoil from the high powered rifle he uses.
Continuity mistake: When Tom traps Jerry in the blinds, he pulls the cord and squashes Jerry. At this point, you can see Tom is holding the cord, but when we Jerry sliding down the blinds in the next shot, Tom is no longer holding the cord.
Factual error: This Warner film concerns a pair of post-Mexican War, new-style percussion revolvers stolen from a travelling arms dealer and used in a crime spree. The criminal was unbeatable because of the overwhelming firepower of the guns compared to the single-shot handguns used by everyone else in the film. The title guns used throughout the film were a pair of Colt Dragoon revolvers, in caliber .44. Colt didn't manufacture a .45 revolver until the metallic cartridge era, in 1873.Mark Schroeder
Visible crew/equipment: When Mr. Gilbert is going to the train station, as he walks around in front of his car, you can see the shadow of the boom mic on the lawn, to the left side of the screen. (01:18:15)
Audio problem: When Daffy says "So long, Rembrandt!" whilst pretending to ride on a bicycle, his beak doesn't move.
Continuity mistake: When Porky inspects Prissy for eggs, you can see that the nest to her has nothing on the wall, but when Porky threatens Prissy to lay an egg, a sign with "Daphne" on it has appeared.