Continuity mistake: Britt is using his right hand to (try to) set his pistol atop a rock (per Jed's request), but the rock is pointed and at an angle. When the camera shifts to a side view, Britt is using his left hand to place the pistol on the rocks and the pointed/angled rock is not there. (01:19:49)
Continuity mistake: When Albert spots the "six riders coming over the ridge", they look closer than when Grandpa stands up to look. The background also looks different (and is mostly blurred to be less obvious). (00:07:18)
Continuity mistake: There is no barn to the left of MacMasters' house (otherwise, it would be visible from the front porch), but when Albert runs from the side of the porch into the open, there is a barn. When Britt got home, there was a barn but it was not where it would have been when Albert was running from Jed's gang. (00:09:10 - 00:10:18)