This revolver and others like it with "US" markings on the trigger guards and mixed numbers are believed to be Civil War contract Model 1860 Army revolvers that were refurbished by the government for use by the U.S. Army, especially the cavalry, out in the West during the Sioux Wars, Yavapai Wars, Texas-Indian Wars, and other conflicts before they were replaced by converted Model 1860 Army, Single Action Army, and Schofield revolvers. They are believed to have been in part issued to the famous "Buffalo Soldiers." Some were likely used to arm Indian scouts and other Native American allies as well in the West. The added "US" markings on the trigger guards may have been added since the "US" markings on the frames are sometimes worn away and as a clear way to distinguish privately purchased arms from government property, especially since former government owned weaponry was also being sold as surplus. It has the usual markings and features of a U.S. contract Model 1860 Army aside from the added marking and mixed numbers on all the components. This example has the three-screw frame and back strap cut for use with a shoulder stock (not included). The frame serial number dates to 1861. The early production barrel is serial numbered "21".