While Hale interrogates Jethro, Govern folds up the letter and puts it back in the envelope. In the next shot, the letter is out again and he folds it up and puts it away again.
Just after the fight between Clinton and Candy, Candy's hair and face magically dry instantaneously.
When the Confederate colonel is reading out the pardons he has granted to the five men, he says that a crime committed by one of the Candy brothers occurred in 1867. Since the film is set in the last months of the Civil War, which ended in 1865, this must be incorrect.
At 45 minutes into the film, when the gang rides into the ranch, the contrail of a modern jet is visible in the background.
When Touch grabs the gun from the uncle at the ranch, the wall he leans on moves a few inches, revealing it as a flimsy set.
Near the end, Haggard has his gun in Clinton's back. Clinton drops his gun and Haggard steps back and mounts his horse. His shadow moves across the back-screen, revealing it as a painted set and not outdoors.