The
20 mm caliber is a specific size of
cannonA cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
or
autocannonAn autocannon or automatic cannon is a rapid-fire projectile weapon firing a shell as opposed to the bullet fired by a machine gun. Autocannons often have a larger caliber than a machine gun . Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded for a...
ammunition, commonly the smallest caliber which is unambiguously a cannon (or more commonly today, autocannon) and not a
heavy machine gunThe heavy machine gun or HMG is a larger class of machine gun generally recognized to refer to two separate stages of machine gun development. The term was originally used to refer to the early generation of machine guns which came into widespread use in World War I...
.
There are few weapons (aside from shotguns and large game hunting rifles) which have been built that fire projectiles between
.50 caliberThe .50 Browning Machine Gun or 12.7×99mm NATO is a cartridge developed for the Browning .50 caliber machine gun in the late 1910s. Entering service officially in 1921, the round is based on a greatly scaled-up .30-06 cartridge...
(0.50 inch/12.7 mm, roughly
13 mm caliberThis article lists firearm cartridges which have a bullet in the caliber range and greater.*Length refers to the cartridge case length.*OAL refers to the overall length of the cartridge.*Bullet refers to the diameter of the bullet....
) and 20 mm caliber, though the
14.5 mmThe 14.5×114 mm is a heavy machine gun and anti-materiel rifle cartridge used by the Soviet Union, the former Warsaw Pact, modern Russia, and other countries....
caliber is used by some Soviet machineguns such as the
KPVThe KPV-14.5 heavy machine gun is a Soviet designed 14.5x114mm-caliber heavy machine gun, which first entered service as an infantry weapon in 1949. In the 1960s the infantry version was taken out of production because it was too big and heavy...
and antitank rifles such as PTRS,
PTRDThe PTRD-41 was an anti-tank rifle produced and used from early 1941 by the Soviet Red Army during World War II. It was a single-shot weapon which fired a 14.5x114mm round...
, and NTW-20.
A very small number of anti-tank rifles have been produced in 20 mm and larger calibers.
20 mm caliber cartridges have an outside shell diameter and inside barrel diameter of 0.79 inch (20 millimeters). Projectiles or shells are typically 75-127 mm (3-5 inches) long. Cartridges are typically 75-152 mm (3-6 inches) long. Many but not all 20 mm shells have an explosive filling and detonating
fuzeFuze Beverage, commercially referred to as just Fuze , is a manufacturer of teas and non-carbonated fruit drinks enriched with vitamins. Currently the brand consists of five vitamin-infused lines: Slenderize, Refresh, Tea, Defensify, and Vitalize...
.
As an example, the 20x102 has a 100 gram bullet fired at a muzzle velocity of 1,035 m/s (3395 ft/s). For a simple slug round this is a muzzle energy of 53,567 joules (or approximately 39,507 ft-lbf).
Usage
Like most cannon ammunition, 20 mm caliber weapons are typically used against large targets such as vehicles, buildings, or aircraft. Though effective against individual soldiers, 20 mm ammunition is so large and heavy that its effects are nearly wasted on relatively small targets.
Types of ammunition
- High Explosive (HE)
- High Explosive Incendiary
In warfare, High-explosive incendiary is a type of ammunition specially designed to pierce armor, fragment, and ignite readily combustible materials....
(HEI)
- Armour Piercing
An armor-piercing shell is a type of ammunition designed to penetrate armor. From the 1860s to 1950s, a major application of armor-piercing projectiles was to defeat the thick armor carried on many warships. From the 1920s onwards, armor-piercing weapons were required for anti-tank missions...
(AP)
- Armour Piercing Incendiary
High Explosive Incendiary/Armor Piercing Ammunition is a form of shell which combines both an armor-piercing capability and a high-explosive effect. In this respect it is a modern version of armor piercing shell...
(API)
- Discarding Sabot Armour Piercing
Armour-piercing discarding sabot is a type of kinetic energy projectile fired from a gun to attack armoured targets. APDS rounds are sabot rounds and were commonly used in large calibre tank guns, but have now been superseded by armour-piercing fin-stabilized discarding sabot projectiles in such...
or proper APDSAPDS may refer to:*Armour-piercing discarding sabot*Androgynous Peripheral Docking System*Augusta Preparatory Day School...
- Target Practice- Inert projectile (i.e., PGU-27A/B). Used for training. (TP)
- Target Practice Tracer- Inert projectile with tracer material in base for visual trajectory tracking (i.e., PGU-30A/B). (TP-T)
Current weapons
- Denel NTW-20
The NTW-20 is a South African anti-materiel rifle or large-calibre sniper rifle, developed by Denel's Mechem division in the 1990s. The weapon was designed by Tony Neophytou and intended for deployment against a wide variety of targets, including parked aircraft, telecommunication masts, power...
: 20×82mm Mauser or 20×110mm Hispano caliber
- GIAT
Nexter is a French government-owned weapons manufacturer.-Products:...
M621The M621 is a 20 mm automatic cannon of French design, developed by Nexter as on-board armament for armored vehicles, aircraft, helicopters and small coastal vessels of the French Navy....
: 20×102mm
- M61 Vulcan
The M61 Vulcan is a hydraulically or pneumatically driven, six-barreled, air-cooled, electrically fired Gatling-style rotary cannon which fires 20 mm rounds at an extremely high rate. The M61 and its derivatives have been the principal cannon armament of United States military fixed-wing aircraft...
: 20×102mm (PGU-28/B)
- M197 Gatling gun
The M197 electric cannon is a three-barreled electric Gatling gun developed primarily for use by United States Army helicopter gunships.Development of the M197 began in 1967 after experience in the Vietnam War revealed the inadequacy of the 7.62 mm Minigun for gunship use...
: 20×102mm
- Pontiac M39
The M39 cannon was a 20 mm caliber single-barreled revolver cannon developed for the United States Air Force in the late 1940s. It was used on a number of fighter aircraft from the early 1950s through the 1980s.-Development:...
: 20×102mm
- RT-20 bolt-action rifle
The RT-20 is a Croatian anti-materiel sniper rifle developed by Metallic in Rijeka in the mid-1990s and marketed by RH-Alan. It was developed to shoot the thermal sights on Serbian M-84 and T-72 tanks. The name itself is actually an acronym of the Croatian word Ručni Top 20 , or "Hand Cannon 20mm"...
: 20×110mm
- Anzio 20mm. Vulcan Anti Material Rifle
The Anzio Sniper Rifle 20mm is the first American anti-materiel rifle to start production with bore diameter in excess of .50 caliber in over 80 years. This series of anti-materiel rifles comes in three basic calibers, 20mm Vulcan, 14.5mm Russian, and recently Anzio 20/50...
- Oerlikon
Rheinmetall Air Defence AG is a division of German armament manufacturer Rheinmetall, created when the company's Oerlikon Contraves unit was renamed on 1 January 2009 and integrated with Rheinmetall's other air-defence products...
KAA & KAB: 20×128mm (formerly the Oerlikon 204GK and 5TG respectively)
- Meroka
The Meroka CIWS is a Spanish Navy 12 barrelled 20 mm CIWS, using twelve Oerlikon 20 mm/120 guns mounted in 2 rows of 6 guns each. The system's primary purpose is defence against anti-ship missiles, and other precision guided weapons. However it can also be employed against aircraft, ships...
: 20x128mm
- Oerlikon KAD
The Hispano-Suiza HS.820 was a 20 mm autocannon developed primarily for aircraft use, but more widely used in a series of ground-based anti-aircraft guns...
: 20×139mm (formerly the Hispano-Suiza HS.820)
- GIAT M693: 20×139mm
- Rheinmetall MK 20 Rh 202
The Rh202 is autocannon with a calibre of 20 mm designed and produced by Rheinmetall.The cannon is used on military vehicles of German origin, like the Marder infantry fighting vehicle, the Spähpanzer Luchs and some variants of the Wiesel AWC...
: 20×139mm
- Vidhwansak
Vidhwansak is an Indian multi-caliber anti-material rifle or large-caliber sniper rifle manufactured by Ordnance Factory, Tiruchirapalli. It can be used in the anti-materiel role for destroying enemy bunkers, lightly armoured vehicles, radar systems, communication equipment, parked aircraft, fuel...
: 20×82mm
- Anzio Sniper Rifle 20mm: 20x102mm
Historical weapons
- Colt Mk 12 cannon
The Colt-Browning Mk 12 was a 20 mm cannon widely used by the United States Navy after World War II.-Development:The Mk 12 was an advanced derivative of the wartime Hispano HS 404 that had been used on a variety of American and British fighter aircraft during World War II...
: 20×110mm (Mk 12 is an advanced derivative of the HS.404)
- Hispano-Suiza HS.404
The Hispano-Suiza HS.404 was an autocannon widely used as both an aircraft and land weapon in the 20th century by British, American, French, and numerous other military services. The cannon is also referred to as Birkigt type 404, after its designer. Firing a 20 mm caliber projectile, it delivered...
and derivatives: 20×110mm
- Hispano-Suiza HS.804: 20×110mm
- Lahti L-39: 20×138mm B (Solothurn Long)
- Rheinmetall
Rheinmetall AG is a German automotive and defence company with factories in Düsseldorf, Kassel and Unterlüß. The company has a long tradition of making guns and artillery pieces...
FlaK 38: 20×138mm B forerunner of Hispano-Suiza HS.820The Hispano-Suiza HS.820 was a 20 mm autocannon developed primarily for aircraft use, but more widely used in a series of ground-based anti-aircraft guns...
post-war 20×139mm round
- Madsen 20 mm anti-aircraft cannon: 20x120mm
- Mauser MG 213
The Mauser MG 213 was a 20 mm aircraft-mounted revolver cannon developed for the Luftwaffe during World War II. It was never put into service, but the principles formed the basis for several post-war developments by the Allies. A 30 mm version was developed as the MG 213C or MK 213 and it was this...
: 20×135mm
- Oerlikon FF
The FF were a series of 20mm autocannon introduced by Oerlikon in the late 1920s. The name comes from the German term Flügel Fest, meaning wing mounted, fixed, being one of the first 20mm guns to be small and light enough to fit into a fighter aircraft's wing...
: 20×72mm RB
- MG FF/M cannon
The MG FF was a drum-fed, 20 mm aircraft autocannon, developed in 1936 by Ikaria Werke Berlin of Germany. It was a derivative of the Swiss Oerlikon FF F cannon, itself a development of the German World War I Becker 20 mm cannon, and was designed to be used in fixed or flexible mountings, as...
: 20×80mm RB
- Mauser MG 151/20
The MG 151 was a 15 mm autocannon produced by Waffenfabrik Mauser starting in 1940. It was in 1941 developed into the 20 mm MG 151/20 cannon which was widely used on many types of German Luftwaffe fighters, fighter bombers, night fighters, ground attack and even bombers as part of or as...
: 20×82mm
- Oerlikon F, FFL
The Oerlikon 20 mm cannon is a series of autocannons, based on an original design by Reinhold Becker of Germany, very early in World War I, and widely produced by Oerlikon Contraves and others...
: 20×100mm RB
- ShVAK: 20×99mm R
- Solothurn S-18/100
The Solothurn S-18/100 20 mm Anti-Tank Cannon was a Swiss & German anti-tank rifle used during the Second World War. It had a semi-automatic action in a bullpup configuration. As a result of its large, powerful ammunition the gun had a tremendous recoil, and its size made portability difficult...
: 20×105mm B
- Solothurn S-18/1000
The Solothurn S-18/1000 20 mm Anti-Tank rifle was a Swiss and German anti-tank rifle used during the Second World War. It was a variant of the earlier S-18/100 with modifications for a higher muzzle velocity, as well as a larger cartridge size...
: 20×138mm B
- Type 99 cannon
The Type 99-1 cannon and Type 99-2 cannon were Japanese versions of the Oerlikon FF and Oerlikon FFL. They were adopted by the Imperial Japanese Navy in 1939 and served as their standard aircraft autocannon during World War II.-Adoption:...
: 20x72RB
Cartridge type indicates the diameter of projectile and the length of the cartridge that holds it, for example 20x102 is a 20 mm projectile in a 102 mm long case. Only rarely do two designers use the same case length, so this designation is usually definitive. Some cartridge types have additional letters or information about them listed.
See also
- :Category:20mm sniper rifles
- .50 BMG
The .50 Browning Machine Gun or 12.7×99mm NATO is a cartridge developed for the Browning .50 caliber machine gun in the late 1910s. Entering service officially in 1921, the round is based on a greatly scaled-up .30-06 cartridge...
- 14.5 × 114 mm
- 20x110mm USN
- 23 mm caliber
- 23 × 115 mm
The 23x115 mm round is used by Soviet/Russian/CIS aircraft autocannon, most notably by the GSh-23L and GSh-6-23. Although the round has been superseded by the 30x165 mm round, the Russian Air Force still uses it in the GSh-23L and GSh-6-23...
- 23 × 152 mm
The 23x152B mm used by the USSR/CIS in the VYa-23 Aircraft Gun on the Ilyushin Il-2 ground attack aircraft and in the 2A7 and 2A14 autocannons on the ZU-23 anti-aircraft gun series and ZSU-23-4 "Shilka", among others...
- 25 mm caliber
The 25x137 mm caliber/.98425 inch is one of the standard sizes of cannon and autocannon ammunition for NATO forces. The round itself has a length of approximately 223 mm .-Usage:...
- 30 mm caliber
30 mm caliber ammunition is usually used in autocannon. Such ammunition includes NATO standard 30 × 173 mm and 30 × 113 mm and Soviet 30 × 165 mm ammunition widely used around the world....
- autocannon
An autocannon or automatic cannon is a rapid-fire projectile weapon firing a shell as opposed to the bullet fired by a machine gun. Autocannons often have a larger caliber than a machine gun . Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded for a...
- caliber
In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
- cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
External links