Approximately, how many types of pistols were used in the U.S. Civil War?

The American Civil War was fought between Union and Confederate forces from 1861 until 1865. During the war, a variety of handguns were used on both sides. Approximately, twenty nine (29) types of handguns were used in the Civil War. They were produced by nineteen weapon manufacturing companies (most were made by the Colt's Manufacturing Company).

The actual models of guns that were used include: Adams Revolver, Beaumont–Adams, Colt Army Model 1860, Colt M1861 Navy, Colt 1851 Navy Revolver, Colt Police, Colt Root, Colt Pocket, Colt Dragoon Revolver, Colt Walker, Colt Paterson, Moore Belt revolver, Remington Model 1858, Smith & Wesson Model 1, Smith & Wesson Model 2, Starr Revolver, Savage 1861 Navy, Tranter Revolver, Kerrs Patent Revolver, LeMat Revolver, Lefaucheux M1858, Butterfield Revolver, Spiller & Burr Revolver, Walsh Revolver, Walch Revolver, Elgin Cutlass Pistol, Volcanic Pistol, Wesson and Leavitt Dragoon Revolver, and Whitney Revolver.

Overall, the Colt .44-caliber “Army" Model 1860 was the most widely used revolver of the Civil War. It was used mostly by the Union forces. The preferred weapon of the Confederacy was the Colt 1851 Navy Revolver. Copies of this weapon were made all over the South in former cotton mills.

During the Civil War, large numbers of casualties were directly caused by the use of firearms (pistols).