20 mm caliber is a specific size of popular autocannon ammunition. The dividing line between smaller-caliber weapons, commonly called "guns", from larger-caliber "cannons" (e.g. machine gun vs. autocannon), is conventionally taken to be the 20 mm round, the smallest caliber of autocannon. All 20 mm cartridges have an outside projectile (bullet) diameter and barrel bore diameter of approximately 0.787 inches (20.0 mm). These projectiles are typically 75 to 127 mm (3–5 in) long, cartridge cases are typically 75 to 152 mm (3–6 in) long, and most are shells, with an explosive payload and detonating fuze.
The usual nomenclature of ammunition indicates the diameter of projectile and the length of the cartridge that holds it; for example, 20×102 mm is a 20 mm projectile in a 102 mm long case.
Though this designation is often assumed to be unique, this is not always the case, e.g. there are three different 20×110 mm types which are not compatible. These may be distinguished in that some cartridge designations may include additional letters or names as a suffix, e.g. the various different types of 20×110 mm might be distinguished as 20×110 mm Hispano, 20×110 mm RB and 20×110 mm USN.
Common suffixesedit
B e.g. 20×138B: the cartridge has a belt which is used for headspacing, i.e. it helps ensure the correct positioning within the gun's chamber.
R e.g. 20×145R: a rimmed cartridge: the diameter of the rim forming the base is larger than that of the cartridge case itself.
RB e.g. Oerlikon 20×110RB: rebated rim, one where the rim is a smaller diameter than the case head allowing the extractor to follow it into the chamber, facilitating advanced-primer ignition, a recoil-moderating system.
^"Otomatik Orta Kalibre Top". 17 October 2022. Retrieved 17 October 2022.
^Williams, Anthony G (January 4, 2021). . Military Guns & Ammunition. Solo Publications. Archived from the original on March 30, 2022. Retrieved April 17, 2022.
External linksedit
FAS: 20 mm Cannon Ammunition
ATK produced 20, 25 & 30 mm caliber ammunition
Rapid Fire: 20 mm Antitank Rifle Cartridges image
Rapid Fire: 20 mm Autocannon Cartridges WWII image 1
Rapid Fire: 20 mm Autocannon Cartridges WWII image 2
Rapid Fire: 20 mm Autocannon Cartridges Post-WWII image
January 01, 1970
caliber, 20mm, redirects, here, model, scale, list, scale, model, sizes, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sour. 20mm redirects here For the model scale see List of scale model sizes This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources 20 mm caliber news newspapers books scholar JSTOR April 2011 Learn how and when to remove this message 20 mm caliber is a specific size of popular autocannon ammunition The dividing line between smaller caliber weapons commonly called guns from larger caliber cannons e g machine gun vs autocannon is conventionally taken to be the 20 mm round the smallest caliber of autocannon All 20 mm cartridges have an outside projectile bullet diameter and barrel bore diameter of approximately 0 787 inches 20 0 mm These projectiles are typically 75 to 127 mm 3 5 in long cartridge cases are typically 75 to 152 mm 3 6 in long and most are shells with an explosive payload and detonating fuze Weapons using this caliber range from anti materiel rifles and anti tank rifles to aircraft autocannons and anti aircraft guns Contents 1 Usage 2 Types of ammunition 3 20 mm weapons 3 1 Current weapons 3 2 Historical weapons 4 Naming conventions 4 1 Common suffixes 5 See also 6 References 7 External linksUsage edit nbsp A 20 102 mm round second from left with 50 BMG rounds golf ball and a stick of 168 pin SDRAM computer memory Twenty millimeter caliber weapons are generally not used to target individual soldiers but rather objects such as vehicles buildings or aircraft Types of ammunition editHigh explosive HE High explosive incendiary HEI Armor piercing AP Semi armor piercing high explosive incendiary SAPHEI Armour piercing discarding sabot APDS High explosive fragmentation tracer HEF T High explosive high capacity HE M Penetrator with enhanced lateral effect PELE Target practice inert projectile i e PGU 27A B 1 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 20 mm weapons editEach weapon is listed with its cartridge type appended Current weapons edit Weapon Country of origin Cartridge Notes Neopup PAW 20 nbsp South Africa 20 42 mm Denel NTW 20 nbsp South Africa 20 82 mm Mauser Denel Vektor GA 1 nbsp South Africa Vidhwansak nbsp India Anzio 20mm rifle nbsp United States 20 102 mm Arash anti materiel rifle nbsp Iran M61 Vulcan nbsp United States M197 electric cannon nbsp United States M39 cannon nbsp United States GIAT M621 nbsp France ZVI PL 20 Plamen nbsp Czech Republic Nexter Narwhal 20A nbsp France Based on the M621 Sahi 20 102 nbsp Turkey XM301 nbsp United States 2 Denel NTW 20 nbsp South Africa 20 110 mm Hispano Metallic RT 20 nbsp Croatia Truvelo CMS 20x110mm nbsp South Africa Yugoimport SDPR M71 08 nbsp Serbia Single barrel development of Zastava M55 Oerlikon KAE KAA KAB nbsp Switzerland 20 128 mm Formerly known as Oerlikon 204GK 5TG Meroka CIWS nbsp Spain Oerlikon KAD nbsp Switzerland 20 139 mm Formerly known as Hispano Suiza HS 820 GIAT M693 20 mm modele F2 nbsp France Rheinmetall Rh 202 nbsp Germany Denel Land Systems GI 2 nbsp South Africa Nexter Narwhal 20B nbsp France Based on the 20 mm F2 Historical weapons edit Weapon Country of origin Cartridge Notes Becker Type M2 20 mm cannon nbsp German Empire 20 70 mm RB Oerlikon FF nbsp Switzerland 20 72 mm RB Type 99 cannon model 1 nbsp Japan Ikaria Werke Berlin MG FF M cannon nbsp Nazi Germany 20 80 mm RB Mauser MG 151 20 nbsp Nazi Germany 20 82 mm Ho 5 cannon nbsp Japanese Empire 20 94 mm Berezin B 20 nbsp Soviet Union 20 99 mm R 3 ShVAK nbsp Soviet Union Helenius RK 20 APH nbsp Finland Derivative of the Helenius RK 97 12 7 mm anti materiel rifle Ghan Krnka fortress rifle nbsp Russian Empire 20 3 95 mm R Bullet diameter 21 mm Type 99 cannon model 2 nbsp Japanese Empire 20 101 mm RB Solothurn S 18 100 nbsp Switzerland 20 105 mm B Bofors m 45 nbsp Sweden 20 110 mm Bofors m 49 nbsp Sweden Hispano Suiza HS 404 and derivatives nbsp Switzerland Oerlikon F FFL nbsp Switzerland 20 110 mm RB Polsten nbsp Poland 20 110 mm RB Colt Mk 12 cannon nbsp United States 20 110 mm USN Advanced derivative of the HS 404 Madsen 20 mm anti aircraft cannon nbsp Denmark 20 120 mm Type 97 automatic cannon nbsp Japanese Empire 20 124 mm Mauser MG 213 nbsp Nazi Germany 20 135 mm Solothurn S 18 1000 anti tank rifle nbsp Switzerland 20 138 mm B Solothurn S 18 1100 anti tank rifle nbsp Switzerland ST 5 20 mm AA gun nbsp Switzerland FlaK 30 and FlaK 38 single barrel AA nbsp Nazi Germany Forerunner of Hispano Suiza HS 820 s post war 20 139 mm round Flakvierling quadruple barrel AA nbsp Nazi Germany MG C 30L aircraft gun nbsp Nazi Germany Rheinmetall KwK 30 and KwK 38 nbsp Nazi Germany Cannone Mitragliera da 20 65 modello 35 Breda nbsp Kingdom of Italy Cannone Mitragliera da 20 77 Scotti nbsp Kingdom of Italy Lahti L 39 anti tank rifle nbsp Finland Solothurn Long Lahti L 40 anti aircraft gun nbsp Finland Nkm wz 38 FK anti tank vehicle mounted gun nbsp Poland Designated heaviest machine gun or Najciezszy karabin maszynowy Nkm AA AT actually an autocannon Type 98 20 mm AA machine cannon and Type 4 20 mm twin AA machine cannon nbsp Japan 20 142 mm Bofors m 40 nbsp Sweden 20 145 mm R Pansarvarnsgevar m 42 nbsp Sweden 20 180 mm R Recoilless rifleNaming conventions editThe usual nomenclature of ammunition indicates the diameter of projectile and the length of the cartridge that holds it for example 20 102 mm is a 20 mm projectile in a 102 mm long case Though this designation is often assumed to be unique this is not always the case e g there are three different 20 110 mm types which are not compatible These may be distinguished in that some cartridge designations may include additional letters or names as a suffix e g the various different types of 20 110 mm might be distinguished as 20 110 mm Hispano 20 110 mm RB and 20 110 mm USN Common suffixes edit B e g 20 138B the cartridge has a belt which is used for headspacing i e it helps ensure the correct positioning within the gun s chamber R e g 20 145R a rimmed cartridge the diameter of the rim forming the base is larger than that of the cartridge case itself RB e g Oerlikon 20 110RB rebated rim one where the rim is a smaller diameter than the case head allowing the extractor to follow it into the chamber facilitating advanced primer ignition a recoil moderating system See also edit 50 BMG 950 JDJ 14 5 114 mm 20 110mm USN 23 mm caliber 23 115 mm 23 152 mm 25 mm caliber 30 mm caliberReferences edit PGU 27A B TP PGU 28A B SAPHEI PGU 30A B TP T Otomatik Orta Kalibre Top 17 October 2022 Retrieved 17 October 2022 Williams Anthony G January 4 2021 Ammunition Data Tables 20 mm Calibre Cartridges Military Guns amp Ammunition Solo Publications Archived from the original on March 30 2022 Retrieved April 17 2022 External links editFAS 20 mm Cannon Ammunition ATK produced 20 25 amp 30 mm caliber ammunition Rapid Fire 20 mm Cartridge Data Table Rapid Fire 20 mm Antitank Rifle Cartridges image Rapid Fire 20 mm Autocannon Cartridges WWII image 1 Rapid Fire 20 mm Autocannon Cartridges WWII image 2 Rapid Fire 20 mm Autocannon Cartridges Post WWII image Retrieved from https en wikipedia org w index php title 20 mm caliber amp oldid 1211087216, wikipedia, wiki, book, books, library,
