Cross, when I was in Montana I shot defensive pistol every week-end at a range between Helena and Butte. It was a well equipped range with silhouettes (paper and mild steel). Defensive pistol allowed modern arms. But on occasion I would go out and shoot the cowboy shoots. Those guys fire their single action revolvers faster than we could from our 1911s. I believe the guy in the film is the one in Butte, Montana who many of our cowboy shooters took their single action colts to for custom tricking. Many of the cowboy shooters are very fancy with their single actions. A 1911 has to cycle and it takes time for the slide to do that. A single action revolver cylinder only turns 1/6 the circumference of the cylinder. Cowboy shooters use ammo that is loaded down, so the effect of recoil is reduced. The trigger is held back and you thumb the hammer (some palm the hammer as Bob does here, but in my opinion thumbing is easier). I always thought those Clint Eastwood movies were just entertainment, not so, there is some fact behind that fantasy. A good single action revolver shooter is NOT at a handicap. Just go watch them sometime. I was able to get decent but not good with my Ruger Blackhawk .44 magnum. In a defensive situation where firepower is not an issue, i.e., someone entering your residence, a single action revolver like a Ruger Blackhawk .44 magnum is not a handicap. The big bore single actions also offer the ability to shoot through walls or armor that some of the smaller semi-auto handguns lack. Of course, hard to beat a double barreled 12 ga. shotgun with 00 buckshot for effect and reliability.
PS: I just searched his name, I confirmed this is the guy who you could take your Colt Peacemaker to and he would do a "Race Job." Meaning he would work the hammer, trigger and change out the springs. I did my own Ruger Blackhawk using a spring kit but I never got serious in the Cowboy shooting but it is loads of fun, including dressing the part, etc. Bob Munden died on the way from Missoula to his home in Butte of a heart attack in 2012.