Revealing mistake: During the barn raise you see the some men using ridiculously small nails to connect huge beams. (01:20:20)
Revealing mistake: After Book shoots McFee, McFee is leaning against the wall with a shotgun in his hand. He is holding a full pump action shotgun with one hand pointed up while wounded and then fires the gun. When he does, there is absolutely no kick to the shotgun at all, revealing it to be a blank shot.
