Editing Revolver (section)

===Single-action===
[[File:Single Action Evolution..jpg|thumb|From Top: Replica of 1849 vintage. .44 Colt Revolving Holster Pistol (Dragoon); Colt Single Action Army Model 1873; Ruger (New Model) Super Blackhawk- Mid and late 20th Century]]

In a single-action revolver, the hammer is manually cocked, usually with the thumb of the firing or supporting hand. This action advances the cylinder to the next round and locks the cylinder in place, with the chamber aligned with the barrel. When the trigger is pulled, it releases the hammer, which fires the round in the chamber. To fire again, the hammer must be manually cocked again. This is called "single-action" because the trigger only performs a single action, of releasing the hammer. Because only a single action is performed and trigger pull is lightened, firing a revolver in this way allows most shooters to achieve greater accuracy. Additionally, the need to cock the hammer manually acts as a safety. With some revolvers, since the hammer rests on the primer or nipple, accidental discharge from impact is more likely if all 6 chambers are loaded. The [[Colt Paterson]], [[Colt Walker]], [[Colt Dragoon Revolver|Colt Dragoon]], and [[Colt Single Action Army]] of the American frontier era are examples of this system.<ref name="forensic" />