Krylandalian, I think I found someting that is right up your alley. Movie is called The Oregon Trail, featuring Arvo Ojala, Hollywood fast draw stuntman, loading, shooting and spinning!! a Colt Walker, explaining as he goes along. Looks to be old repros as the film is from 1959.
I watched the scene closely again, from what I can see the revolver is swapped between loading and shooting scenes for a Remington New Model Army.
Of course the loading sequence leaves something to be desired as the revolver is taken apart for loading, and doesn't apply the percussion caps.
At 50:10 the loading sequence:
Later there's a final battle where the Walkers are used against Indians in a large fight. If you watch closely there are also a lot of Remington New Model Army's used. Fight is at around 1:12:00.
Not the greatest movie but fun to watch.