Factual error: The gatling gun that Josey Wales uses had the options of a 40 round magazine, or a 104 round drum magazine. Neither Josey or the Red Legs ever bothered to reload the weapon. The gun would have been empty after the 10 barrels revolved at most 10 times. Josey alone shoots for a couple of minutes straight.
Factual error: The movie takes place in year 1865, when the U.S. Civil War ended. In the scene, where Lone Watie sneaks up on Josey and Moonlight sneaks up on Lone, the revolvers that both Native American actors are wielding, are equipped with Richards-Mason cartridge conversion kits, you can see the ejector-rod housing on the right side of the barrel. These conversions were not made until 1870's.Other characters as well use these conversion-revolvers throughout the movie.