The Colt 1860 Army is used in the show by US soldiers and the Man in Black in the episode "The Adversary".[1]
Background[]
The Colt Army Model 1860 is a muzzle-loaded cap & ball .44-caliber single-action revolver used during the American Civil War made by Colt's Manufacturing Company. It was used as a side arm by cavalry, infantry, artillery troops, and naval forces.
More than 200,000 were made between 1860 and 1873, the majority of which were supplied to the US military.