Character mistake: When Vallian prepares to leave the homestead, McKaskell asks him how his chest wound was. Vallian was shot low on the right side, just above the gun-belt, and McKaskell, who removed the bullet, was quite aware of the location.
Continuity mistake: As Jesse, Diamondback and Homer try to black out the windows on their car (to protect themselves from the sunlight) Homer spray paints the window next to him black. The camera angle switches to a wide shot as the car drives by. At this time, the back window (which was just blacked out) has not been spray painted yet. It is totally clean again.