The ShKAS (Shpitalny-Komaritski Aviatsionny Skorostrelny, Shpitalny-Komaritski rapid fire for aircraft; Russian: ШКАС - Шпитального-Комарицкого Авиационный Скорострельный) is a 7.62 mm calibre

machine gun A machine gun is a fully automatic, rifled autoloading firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles (including assault rifles and battle rifl ...

widely used by

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...

aircraft in the 1930s and during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. The ShKAS had the highest rate of fire of any aircraft machine gun in general service during WWII. It was designed by Boris Shpitalniy and Irinarkh Komaritsky and entered production in 1934. ShKAS was used in the majority of Soviet fighters and

bomber A bomber is a military combat aircraft designed to attack ground and naval targets by dropping air-to-ground weaponry (such as bombs), launching aerial torpedo, torpedoes, or deploying air-launched cruise missiles. The first use of bombs dropped ...

s and served as the basis for the

ShVAK The ShVAK ( ru , ШВАК: Шпитальный-Владимиров Авиационный Крупнокалиберный, Shpitalnyi-Vladimirov Aviatsionnyi Krupnokalibernyi, "Shpitalny-Vladimirov Aviation Large-calibre") was a 20 mm autocanno ...

cannon.

Description

ShKAS is a

gas-operated Gas-operation is a system of operation used to provide energy to operate locked breech, autoloading firearms. In gas-operation, a portion of high-pressure gas from the cartridge being fired is used to power a mechanism to dispose of the spen ...

revolver-type

; it has a single chamber in which the pin strikes the primer. A key element of the ShKAS' high rate of fire is the revolving drum (feed cage) that holds ten rounds and provides a very smooth, progressive removal of the cartridges from their disintegrating link belt. The bolt locking action is Browning-style, i.e. slightly tilted wedge bolt. The bolt action mechanism is the "gas piston in a tube - rod - bolt frame", rather similar to Kalashnikov's assault rifle. The main difference with AK is that, with AK, the whole assembly of piston-rod-bolt frame is a single large and heavy part. And, with ShKAS, it is split to several parts - the piston, the rod and the bolt frame, with a "personal" recoil spring for each of them (the weapon has a lot of springs in it). This provided for the lightweight recoiling portion of the gun, which weighs only 921 grams (2.07 lb). Diagram of the ShKAS feed system operation - en

Diagram of the ShKAS feed system operation - en

A declassified US analysis of the feed system, based on models captured during the

Korean War {{Infobox military conflict , conflict = Korean War , partof = the Cold War and the Korean conflict , image = Korean War Montage 2.png , image_size = 300px , caption = Clockwise from top: ...

, reads:Chinn, pp. 78–79 ( Ian V. Hogg called the ShKAS feeding system a " squirrel cage".) After analysing the less unusual parts of the ShKAS, the US source concludes: Although ShKAS is best known for its high rate of fire, it did have provision for slower cyclic rates by lowering the gas-pressure. This was done by "changing the position of the holes in the gas regulator, which comes with holes of three different sizes: 2.1 mm (1/12-inch), 2.5 mm (1/10-inch) and 3.2 mm (1/8-inch). The smaller the orifice used, the more moderate is the rate of fire obtained."

Variants

Initial production consisted of cable-charged wing-mounted and turret-mounted ShKAS with a synchronized version entering service in 1936. By 1952 Western intelligence had identified five different models, all including the number "426" in their markings:Chinn, p. 72 * a prototype "426" appeared in 1932 * KM-33, in flexible role, appeared in 1933 * KM-35, in flexible role (1934) and wing-mounted (1935) * KM-36, in flexible role (1935) and propeller-synchronized (1937); the latter had an extra-long barrel * a 1941 model, wing-mounted "KM" stands for "constructed model", i.e. production. The intended role was marked with the letters "T" for flexible, "K" for wing, and "S" synchronized. The flexible version was usually mounted in a Soviet copy of the

Scarff ring The Scarff ring was a type of machine gun mounting developed during the First World War by Warrant Officer (Gunner) F. W. Scarff of the Admiralty Air Department for use on two-seater aircraft. The mount incorporated bungee cord suspension in el ...

.Chinn, p. 73 The 1937 model had slightly higher maximum rate of fire of 2,000 rounds per minute. The amount of ammunition normally carried was 750 rounds for the fixed models and 1,000 to 1,500 for the flexible. Soviet archives indicate the following production volumes, by year: * 1933 — 365 produced * 1934 — 2,476 * 1935 — 3,566 * 1937 — 13,005 * 1938 — 19,687 * 1940 — 34,233 * 1943 — 29,450 * 1944 — 36,255 * 1945 — 12,455 In 1939, a small number of Ultra-ShKAS were produced featuring a firing rate of 3,000 rounds per minute but these saw only limited use due to reliability problems.

Effectiveness

The ShKAS was the fastest-firing rifle calibre aircraft armament in general service in World War II. A one-second burst from the four ShKAS of a

Polikarpov I-153 The Polikarpov I-153 ''Chaika'' (Russian ''Чайка'', "Seagull") was a late 1930s Soviet biplane fighter. Developed as an advanced version of the I-15 with a retractable undercarriage, the I-153 fought in the Soviet-Japanese combats in Mon ...

Polikarpov I-16 The Polikarpov I-16 (russian: Поликарпов И-16) is a Soviet single-engine single-seat fighter aircraft of revolutionary design; it was the world's first low-wing cantilever monoplane fighter with retractable landing gear to attain o ...

placed 120 bullets within 15

angular mil A milliradian ( SI-symbol mrad, sometimes also abbreviated mil) is an SI derived unit for angular measurement which is defined as a thousandth of a radian (0.001 radian). Milliradians are used in adjustment of firearm sights by adjusting ...

s at 400 meters (1,312 feet) giving a firing density of 5 bullets per square meter of the sky. Moreover, the ShKAS was unusually light as well; the four guns, with 650 rounds of ammunition each, weighed a total of only 160 kg (350 lb). ShKAS wasn't problem-free though. Soviet machine-gun technician Viktor M. Sinaisky recalled:

Gun specifications

* Cartridge: 7.62×54mmR * Calibre: *

Rate of fire Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. This can be influenced by several factors, including operator training level, mechanical limitations, ammunition availability, and weapon condition. In m ...

: 1,800 rounds/min wing- or turret-mounted; 1,625 rounds/min synchronized. UltraShKAS: 3,000 rounds/min. *

Muzzle velocity Muzzle velocity is the speed of a projectile (bullet, pellet, slug, ball/ shots or shell) with respect to the muzzle at the moment it leaves the end of a gun's barrel (i.e. the muzzle). Firearm muzzle velocities range from approximatel ...

: *

Weight In science and engineering, the weight of an object is the force acting on the object due to gravity. Some standard textbooks define weight as a vector quantity, the gravitational force acting on the object. Others define weight as a scalar q ...

: empty; with 650 rounds of ammunition.

7.62 mm ammunition specifications

Although chambered in the 7.62×54mmR, the ShKAS guns used cartridges specially built for them to smaller tolerances; to distinguish them from the regular 7.62 ammunition, the Cyrillic letter "Sh" ( Ш) was imprinted on the bottom of the cases. The cases, designed by N. M. Elizarov, also had a few additional features like double crimping and a thicker case wall of "bimetallic" construction instead of the traditional

brass Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other wit ...

. The main type of bullet used was

armour-piercing incendiary Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour. From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many wa ...

B-32 bullet. Ammunition marked as such should not be fired out of any regular 7.62x54mmR rifles. * Bullet weight: 148 grains (9.6 grams) * Round weight: 370 grains (24 grams) *

Ballistic coefficient In ballistics, the ballistic coefficient (BC, ''C'') of a body is a measure of its ability to overcome air resistance in flight. It is inversely proportional to the negative acceleration: a high number indicates a low negative acceleration—the ...

: 2,100 kg/m² (3.0 lb/in²) *

Tracer ammunition Tracer ammunition (AMO) (Tracers) are bullets or cannon-caliber projectiles that are built with a small pyrotechnic charge in their base. When fired, the pyrotechnic composition is ignited by the burning powder and burns very brightly, making th ...

duration: 750 m (2,460 ft) * Armour piercing: 11 mm (0.43 in) at 400 m (1,312 ft)

Possible influences

Some military historians believe the feed system of the Mauser 213C (the seminal

revolver cannon A revolver cannon is a type of autocannon, commonly used as an aircraft gun. It uses a cylinder with multiple chambers, like those of a revolver handgun, to speed up the loading-firing-ejection cycle. Some examples are also power-driven, to fu ...

for Western designs) was inspired by the ShKAS. George Chinn 1951, The Machine Gun: Development During World War II and Korean Conflict by the United States and their Allies of Full Automatic Machine Gun Systems and High Rate of Fire Power Driven Cannon, Volume III, Parts VIII and IX. p. 44 However, the method of operation is very different: gas-operation on the ShKAS versus a revolving cam on the MG 213C.

Users

* *

Second Spanish Republic The Spanish Republic (), commonly known as the Second Spanish Republic (), was the form of government in Spain from 1931 to 1939. The Republic was proclaimed on 14 April 1931, after the deposition of King Alfonso XIII, and was dissolved on 1 ...

References

;Notes ;Bibliography * Drabkin, Artem. ''The Red Air Force at War: Barbarossa and the Retreat to Moscow – Recollections of Fighter Pilots on the Eastern Front''. Barnsley, South Yorkshire, UK: Pen & Sword Military, 2007. . * Романов Д. И. Оружие Воздушного Боя (Romanov D.I., ''Aerial Weapons'') * Chinn, George M. The Machine Gun, Vol II, Part VII. US Department of the Navy, 1952 * Широкорад А.Б. (2001) ''История авиационного вооружения'' Харвест (Shirokorad A.B. (2001) ''Istorya aviatsionnogo vooruzhenia'' Harvest. ) (''History of aircraft armament'')

External links

Ultra-ShKAS photo

патроны для сверх пулемета
{{Russian and Soviet Aircraft Ordnance Medium machine guns World War II machine guns 7.62×54mmR machine guns Machine guns of the Soviet Union Cold War firearms of the Soviet Union Aircraft guns of the Soviet Union KBP Instrument Design Bureau products Military equipment introduced in the 1930s