The cocking handle, also known as charging handle or bolt handle, is a device on a firearm which, when operated, results in the hammer or striker being cocked or moved to the ready position. It allows the operator to pull the bolt to the rear. The cocking handle has a number of functions: it facilitates the ejection of a spent shell casing or unfired cartridge from the chamber; it loads a round from the magazine or by hand through the chamber; it clears a stoppage such as a jam, double feed, stovepipe or misfire; it verifies that the weapon's chamber is clear of any rounds or other obstructions; it moves the bolt in to battery, acting as a forward assist ; it releases a bolt locked to the rear, such as would be the case after firing the last round on a firearm equipped with a last-round-hold-open feature. These devices vary significantly between firearms but may occur in the form of a small protrusion or hook from the side of the bolt, a pumped slide or lever. The slide in a pistol performs similar actions as a cocking handle. There are also additional factors concerning the design of cocking handles, and some of them are especially important if the weapon is for tactical use. One issue is the mean time between failures due to metal fatigue. Just like other parts, cocking handles sometimes break when weapons are heavily used. Another issue is whether the cocking handle is sufficiently large for use by someone wearing heavy gloves and protective clothing. Some weapons are designed with thumb grooves for extra grip when cocking a weapon to prevent releasing it before it has been pulled back all the way, such as the British SA80 family of rifles. Cocking handles can be reciprocating or non-reciprocating. The advantage of the former is that it gives the user complete control over the movement of the bolt and bolt carrier, and it enables great force to be used to chamber or extract difficult or ruptured cartridges. However it adds an extra, fast-moving part on the outside of the gun and may limit the way the gun is handled.
