I watched the video, not too bad for a first attempt.
I get it you didn't have any .45 Colt so you used .44mag for dummies. It would have been better if you had gotten (made) dummies from .45 Colt cases, that way there would be nothing confusing.
You had an SAA, why didn't you use that, instead of the Bisley model??
The mechanisms are identical, the Bisley differs only in the shape of the trigger, hammer, and grip frame. (also often Bisleys have "target" sights)
small technical terminology critique; couple times you refer to the head of the case or the side of the head, where the firing pin strikes are. The correct term for that location is the rim, not the head, and those strikes are on the edge of the rim, not the side.
It can be correct to refer to the bottom where the markings are, as the "base of the case" and the portion of that which sticks out beyond the diameter of the case body is the rim.