Vince - I think you are mixing up the film “Unforgiven” with some other film. In “Unforgiven” Clint Eastwood carried an old Star revolver, and a side-hammer double-barrel shotun. His Black side-kick, of age similar to Eastwood, carried a Spencer carbine, later used by Eastwood in the bar room fight. I don’t remember what revolver the Black fellow used, or if he even had one. The young side-kick carried a Schofield Revolver. There were other guns in the movie, including the usual Colt SAAs, Winchester-type rifles, and the Englishman also had a .32 hid-out top-break revolver. Good assortment.
As to Eastwoods .44 Magnum, he probably could have gotten away with it as an Inspector, but it was not up to San Francisco Police Regulations of the time, which called for a blued steel, natural grips. six-shot, 4" or 6" barrel revolver (2" ok for inspectors, backup guns, off duty guns, etc.) .38 or .357 magnum revolver, Colt or Smith and Wesson make. Guns were issued, but officers could carry their own if it met regs. That said, I had a customer, a solo officer (motorcycle officer) who was 6 foot 7 inches tall, and a big guy in build (muscle, not fat). Because of his size, no one seemed to notice that the carried an 8-3/8" barreled Model 29 Smith and Wesson .44 Magnum, loaded with .44 Magnum, and he wore it in a low riding duty-style holster.
In one movie, Eastwood mentions that he uses the .44 Magnum usually with .44 Special loads. I forget which one it was, but probably one of the later ones. In the early ones, it was obvious from the “kick” done by him - nice touch, one of the first actors to show a pistol having recoil-that he was supposed to e shooting .44 Mags. He alluded to that caliber often, also. In one movies, he used a .44 Auto Mag pistol, or a Wildey .475. Mag, I forget which.
Movies have gotten much more accurate about a lot of things, and plenty of it is thanks to regular shooters - non-hollywood guys. Cowboy Action Shooting has had a big effect on the guns used in Western movies, and also on the clothing worn, and other equipment used. Civil War reenactors have had a huge effect on movies of that period, including the hiring of entire civil war reenactment groups to perform in them - a director’s dream, as they all have their own weapons, uniforms and equipment, and in some cases, their own horses. They have made civil war movies a helluva lot more realistic and accurate.
Of course, firms like Uberti making replicas of all manner of early Winchesters, Spencers, Muskets, etc., have helped a lot. I remember when every civil war movies, the standard “musket” was a .45-70 Trapdoor Springfield, and in every Western you saw two guns - single action Colts and Model 1892 Winchesters, sometimes showing each used in movies taking place even before the Civil War of 1860-1865.
Interesting topic. Movie blanks are interesting too. All manner of them, as has been discussed here before - difference noise levels, different flash durations, etc.