Goofs

When the trio leave O.W.'s house with the wagon, in the long shot Jed is riding a horse behind the wagon while pulling another horse. In the next shot of him with the camera looking out the back of the wagon, Jed is riding the horse but not pulling a second horse.

Laura Breckenridge drives a wagon laden with hay to the bank. It's about 8-9 feet long. When Sam, O.W., and Jed all drop from an upper floor of the bank into the hay wagon, they appear to be about 18-24 inches tall compared to the length of the wagon.

O.W. had Sam Whiskey shoot his Gatling-style gun, but Sam was hitting below the targets. O.W. said he was adjusting for Sam's eyesight and raised the front sight, but then he shot it himself and hit the targets. Raising the front sight would lower the trajectory of the bullets even further, not raise it. And the adjustment was for Sam's eyes, not O.W.'s, yet O.W. was the one who shot the gun and hit the targets after raising the front sight.

The steamboat's smokestack was wobbling back and forth in the river current when the guys first saw it. A steamboat smokestack wouldn't still be standing against the river current if it were that loose.

That was an optical illusion caused by the flow of the river. The stack didn't move.

In the early fight with the blacksmith, Sam is hit but still has his cigar firmly in his mouth. When he lands, it is gone.

The possibility exists that the cigar was knocked out of frame after the punch. It can't actually be seen between the punch and the landing. In terms of the movie, that's what happened.

At the very end of the movie, just before the credits roll there is a long shot of the train. The two passenger cars are obviously empty.