Machine pistol

A machine pistol is a submachine gun that is capable of automatic fire in the form of a handgun. Machine pistols are magazine-fed and self-cocking. These weapons are capable of automatic or burst fire, and being the size of a pistol are able to be held - but usually not fired - comfortably in one hand. The 1932 Mauser Model 712 'SchnellFeuer', a modification of Mauser's 1896 design, is notable as the first widely accepted and mass-produced machine pistol.

However, firing such pistols in fully automatic mode is notoriously difficult for the user to control, on account of the weapons' light weight and lack of grips for both of the user's hands. This led to the development of an "intermittent-fire" setting that fires a burst of three shots instead of full-automatic. The first pistol developed with the three shot system might be the Heckler & Koch VP70.

The term "machine pistol" is a literal translation of Maschinenpistole, the German term for a submachine gun. While the term existed previously as a synonym for semi-automatic pistols, Western references to automatic machine pistols appear at least as early as 1935.

While there is no uniform set of defining characteristics of the type, being chambered for a pistol cartridge and being capable of firing more than one round per trigger pull are two of the features of a machine pistol. Many have a magazine contained within the grip, and several have select-fire capabilities. Some machine pistols only fire three-shot bursts, such as the Beretta 93R or the Heckler & Koch VP70. The VP70 is capable of semi fire. The only way to get the 3 round burst is with the stock attached. However, most are simply fully automatic.

The difference between machine pistols and submachine guns is ill-defined and often misunderstood. Usually the term submachine gun refers to larger automatic firearms. Today several types of weapon are described as either - for instance the MAC-10 and the smaller examples of the Uzi series. Typically, however, a submachine gun's operating mechanism is scaled down from that of a full-sized machine gun, while a machine pistol is built up from a semi-automatic pistol design.

The popularity of submachine guns in recent years has led many weapons previously described as machine pistols to be advertised and referred to as submachine guns. Perhaps the most obvious example is the Brugger & Thomet MP-9, which was formerly known as the Steyr TMP.

Though many submachine guns possess a stock and are thus capable of being fired from the shoulder like a rifle, this is not a clearly defining feature, as numerous submachine guns lack a stock, and several machine pistols possess them, at least as optional extras.

Machine pistols are sometimes preferred by undercover operatives for their small size and high rate of fire. Specialist units such as SWAT also use machine pistols on occasion, mostly inside buildings and other cramped spaces.