Revolvers
Revolvers received their name from the rotating cylinder that holds the cartridges. The cylinder can hold up 5-7 bullets. However, there are some revolvers (usually the .22 caliber) that can hold from 8 to 10.
Loads in the cylinder may be reloaded in 2 ways (depending on revolver design) - one by one, as, for example, the Colt PeaceKeeper does (and almost all old-timers), or all simulateounosly - when the cylinder is switched to the side or when the is frame “broke open.” Both revolvers and semi-autos have two main “action styles”: Single action and Double action.
Single Action means, that the Revolver must be manually cocked (and, thus, the cylinder is rotated to the next cartridge) for each shot. This mode was the only one available in all old-time revolvers (such as the Peacekeeper), and is still available in most double-action revolvers. This mode improves accuracy but slows the fire rate. For Semi-autos, Single Action means that the pistol must be manually cocked for the first shot (usually, this is done by pulling the slide - this action cocks the hammer and feeds a cartridge into the chamber). For the second, and all consecutive shots, cocking is done automatically, when recoil force pulls back the slide.
Double Action for the Revolver means that the hammer for each (including the f irst) shot is cocked by trigger pull (this action also rotates the cylinder to the next position). This mode speeds up the firing rate and simplifies shooting actions, but greatly increases trigger pull (from 2.2-4.4 lbs usually found in single-actions, to 8.8-12.2 lbs in double-actions). For the Semi-autos, the hammer is usually cocked by trigger pull for the first shot only; the second and the rest are done in single-action mode. However, first load must be fed in the chamber by the slide pull. Some (most of them - compact) semi-autos and revolvers employ Double-action-only mode, which cocks the trigger for each shot, thus excluding single-action.