When Bill Doolin hands a shotgun shell to the kid who wants to watch the approach to the town for him, he hands him a standard red 12-gauge shotgun shell that any 12-gauge owner today would know well, but it was only in the late 1960s that manufacturers began using a color-coding scheme, originally red for 12-gauge, gold for 20-gauge. In 1890s Oklahoma it would not have been the color shown on screen.