Lucas rides into town. He gets off his horse. He walks into the hotel wearing a jacket he didn't have on when he rode into town.
Mark's .22 rifle seen at the end of the episode is not the same rifle he got three episodes earlier, in Mark's Rifle (1962). That rifle was a Model 1890 Winchester, but this one is a Model 1906.
When Mark goes behind the hotel counter to hopefully get the rifle for Lucas, when he looks at it, it's not the same rifle as the one Lucas placed there earlier. It's leaning at a different angle, and the loop ring has a slightly different shape to it. They must have used stock footage from an earlier episode for this shot.
When the rifle fires a shot during the scuffle and kills Mark's friend, the barrel is pointed far to the left, nowhere near where the victim is standing.