He walked up to the lieutenant's office, leaned wearily against the gun rack that housed four rifles and a gas gun nobody remembered having used and a submachine gun that was occasionally tried out on the Academy Range.

Ultimately, the Saville Inquiry was inconclusive on Martin McGuinness's role due to a lack of certainty over his movements, concluding that while he was " engaged in paramilitary activity " during Bloody Sunday, and had probably been armed with a Thompson submachine gun, there was insufficient evidence to make any finding other than they were " sure that he did not engage in any activity that provided any of the soldiers with any justification for opening fire ".

61 submachine gun

* PDW Škorpion EVO III submachine gun

* Heckler & Koch MP5 submachine gun

Being larger than a submachine gun, they are harder to maneuver in tight encounters where superior range and stopping power at distance are not great considerations.

In addition, due to the development of body armor, support personnel required a compact weapon with more penetration than the traditional submachine gun, leading to the development of the personal defense weapon, or PDW, which uses rounds that have better ballistics than simple pistol rounds but less power and range than full rifle rounds.

Another class of carbine is a semi-automatic version of a submachine gun, with an extended barrel, usually just over 406 mm ( 16 inches ) long, which will escape ban by some " assault weapon " legislation.

These are a popular compromise for ( American ) shooters who would like to own a submachine gun but cannot due to local restrictions or the prohibitive cost of buying a civilian legal submachine gun ( full automatics or semi-automatics with barrels shorter than are restricted under Title II of the National Firearms Act ).

Examples of PCCs that are derivatives of submachine guns but are rifles under Title I ( Gun Control Act ) include the HK USC ( derived from the HK. 45ACP UMP submachine gun ), the HK94 ( derived from the MP5 ), pistol-caliber AR-15s ( such as the Bushmaster Carbon 15 9 mm Carbine ), semi-automatic only versions of the Thompson by Auto-Ordnance and the FN PS90 ( derived from the FN P90 SMG ).

The semi-automatic only version of the Sterling submachine gun was also officially called a " carbine ".

Most automatic weapons are classed as long guns ( as the ammunition used is of similar type as for rifles, and the recoil of the weapon's rapid fire is better controlled with two hands ), but handgun-sized automatic weapons also exist, generally in the " submachine gun " or " machine pistol " class.

Well-known examples are the Israeli Uzi and Heckler & Koch MP5 which use the 9 × 19mm Parabellum cartridge, and the American Thompson submachine gun which fires. 45 ACP.

The most widely used submachine gun at the end of the 20th century was the Heckler & Koch MP5.

A related class of firearm to the submachine gun is the " Personal Defense Weapon " or PDW, which is in simplest terms a submachine gun designed to fire rounds similar to rifle cartridges.

The MP5 is actually designated as a " machine pistol " by Heckler & Koch ( MP5 stands for Maschinenpistole 5, or Machine Pistol 5 ), although some reserve this designation for even smaller submachine guns such as the MAC-10 and Glock 18, which are about the size and shape of pistols.

A submachine gun is desirable for its compact size and ammunition capacity, however a pistol round lacks the penetrating capability of a rifle round.

Conversely, rifle bullets can pierce light armor and are easier to shoot accurately, but even a carbine such as the Colt M4 is larger and / or longer than a submachine gun, making it harder to maneuver in close quarters.

The solution many firearms manufacturers have presented is a weapon resembling a submachine gun in size and general configuration, but which fires a higher-powered armor-penetrating round ( often specially designed for the weapon ), thus combining the advantages of a carbine and submachine gun.

In contrast to submachine guns and autocannons, machine guns ( like rifles ) tend to share the characteristic of a very high ratio of barrel length to caliber ( a long barrel for a small caliber ); indeed, a true machine gun is essentially a fully automatic rifle, and often the primary criterion for a machine gun as opposed to an automatic rifle is the presence of a quick-change barrel or other cooling system ( see below ).

While the dividing line between machine pistols and compact submachine guns is hard to draw, the term " submachine gun " usually refers to larger automatic firearms scaled down from a full-sized machine gun to fire handgun rounds, while the term " machine pistol " usually refers to a weapon built up from a semi-automatic pistol design.

The UZI submachine gun upon which the Micro-Uzi is based was developed in Israel by Uziel Gal in the late 1940s.

The dividing line between machine pistols and compact submachine guns is difficult to draw.

The 1960s CZ-Scorpion, a Czechoslovak 7. 65 mm weapon, for example, is often labeled a submachine gun.

The Steyr TMP ( Tactical Machine Pistol ) is a 9 mm blowback-operated, rotating-barrel weapon that is 282 mm long and that can fire 800 – 900 rounds per minute ; despite its small size, lack of a stock, and the fact that it is called a " tactical machine pistol ", it is often classed as a compact submachine gun.

This " select-fire " capability, as well as the ( general ) use of magazine-fed rifle ammunition, differentiate it from other classes of automatic firearm such as the machine gun and submachine gun.

The UMP is a blowback operated, magazine-fed submachine gun firing from a closed bolt.

In the 2000s, the machine pistol started to be supplanted by the personal defense weapon: a compact, fully automatic submachine gun-like firearm which fires armour-piercing rounds instead of pistol ammunition.

In the 1990s and 2000s the personal defense weapon, a compact submachine gun-like firearm which can fire armor-piercing, higher-powered ammunition began to replace the machine pistol as a self-defence side arm for artillery crews, tank crews, and helicopter pilots ( for more details, see the section below on military tactics ).

While the term submachine gun usually refers to an automatic firearm larger than a pistol, several weapons are classed in both categories.

As a result, armies began to issue a new weapon to artillery crews and tank crews: the personal defense weapon, a compact submachine gun-like firearm which incorporates some of the advantages of a carbine, in that it can fire armor-piercing, higher-powered ammunition.

The requirement for the new firearm called for a compact, lightweight defensive weapon with an effective range of 300 yards, with greater range, firepower, and accuracy than the pistol, while weighing half as much as the Thompson submachine gun or M1 rifle.

A personal defense weapon ( PDW ) is a compact semi-automatic or fully automatic firearm similar in most respects to a submachine gun, but firing a ( often proprietary ) rifle round, giving a PDW better range, accuracy and armor-penetrating capability than submachine guns, which fire pistol-caliber cartridges.

A firearm using detachable magazines may accept a variety of types of magazine, such as the Thompson submachine gun, which would accept box or drum magazines.

Weapon mounted lights used to be specific to particular models of firearm, and to some extent that is still true ; for example, SureFire makes dedicated lights that replace the forends of the Mossberg 500 and Benelli M3 shotguns, the Heckler & Koch MP5 submachine gun, and the M4 carbine.

* OVP ( firearm ) 9mm Glisenti submachine gun

* The Goblin submachine gun, a Ukrainian firearm

Some firearms, such as some versions of the Thompson submachine gun, have a forward pistol grip which is used to stabilize the firearm in operation.

* Machine pistols and submachine guns ( like the World War II " grease gun ", MAC-10 or the Uzi ) are usually blowback operated.

The description is usually limited to revolvers, pistols, submachine guns, carbines, assault rifles, battle rifles, multiple barrel firearms, sniper rifles, squad automatic weapons, light machine guns ( e. g. M60 ), and sometimes hand grenades.

Although America used box magazines in the Thompson, and Soviet submachine gunners carried only a few drum magazines ( usually one drum, if any, and remaining ammunition as box magazines ), the Suomi was mostly deployed with drums.

He usually carried a pistol or a Thompson submachine gun.

They are usually armed with electroshock batons and pistols, and are occasionally seen using submachine guns.

* Assault team: Made up of soldiers usually with the M1A1 Carbine and the Thompson submachine gun and is good for flanking the enemy while they are pinned down by the players fire team.

Whilst the submachine gun replicas typically feature a blowback mechanism similar to the pistol replicas, sniper rifle replicas usually omit the blowback mechanism in favor of reduced recoil and increased muzzle velocity.

These units were all highly trained and indoctrinated, skilled in demolitions and small-unit tactics, they would usually operate in small teams of 2-12 men, lightly armed with either PPS submachine guns or AK-47s.