The 45 mm anti-aircraft gun (21-K) was a Soviet design adapted from the 45 mm anti-tank gun M1932 (19-K). This was a copy of a 3.7 cm (1.5 in) German weapon designed by Rheinmetall that was sold to the Soviets before Hitler came to power in 1933 that had been enlarged to 45 mm (1.8 in) to reuse a large stock of old 47mm ammunition. It was used by the Soviet Navy to equip almost all of their ships from 1934 as its primary light anti-aircraft gun until replaced by the fully automatic 37 mm 70-K gun from 1942 to 1943. It was used in World War II and during the Cold War as the Soviets exported their World War II-era ships to their friends and allies. However it was not very effective as its slow rate of fire and lack of a time fuze required a direct hit to damage targets.
The 46-caliber21-K was a minimal adaptation of the 53-K anti-tank gun that was created by taking the latter's barrel and mounting it on a simple pedestal mount. Its semi-automatic breech automatically ejected the cartridge case and locked open, ready for the next round. This was less than ideal for an anti-aircraft weapon that relied on its rate of fire to inflict damage on aircraft because every round had to be hand-loaded.[1] Fully automatic weapons of roughly this caliber like the 40 mm Bofors typically used 4-5 round clips of ammunition to produce rates of fire four times as high.
Early production guns had a built-up barrel, but later ones used a monobloc. There were problems with the breech mechanism early in the production run and a number of the first year's production run lacked the semi-automatic breech entirely.[2]
DescriptionEdit
The 21-K, complete with its pedestal, weighed 507 kg (1,118 lb). It was manually operated and could elevate between -10° and +85° at a rate between 10 and 20 degrees per second. It could traverse a full 360° at a rate between 10 and 18 degrees per second, although this was practically limited by its actual location on ship. In the mid-1930s special powered turrets were developed for use on river monitors. The 40-K was a single gun turret that weighed 2,000 kg (4,400 lb) and the 41-K was a twin-gun turret that weighed 2,600 kg (5,700 lb). Both turrets could elevate between -5° and +85° at a rate of 8 degrees per second and could traverse a full 360° at a rate between 4.8 and 9.8 degrees per second.[2]
AmmunitionEdit
The 21-K used the same ammunition as the 45 mm anti-tank gun M1937 (53-K). The biggest problem in its role as an anti-aircraft gun was that it wasn't provided with a time fuze that would detonate the shell at a specified distance from the gun. This meant that only a direct hit would damage its target.[2]
Campbell, John (2002). Naval Weapons of World War Two. London: Conway Maritime Press. ISBN0-87021-459-4.
Koll, Christian (2009). Soviet Cannon - A Comprehensive Study of Soviet Arms and Ammunition in Calibres 12.7mm to 57mm. Austria: Koll. p. 441. ISBN978-3-200-01445-9.
External linksEdit
Media related to 45mm/46 21-K gun at Wikimedia Commons
K-21 on navweaps.com
October 17, 2023
anti, aircraft, soviet, design, adapted, from, anti, tank, m1932, this, copy, german, weapon, designed, rheinmetall, that, sold, soviets, before, hitler, came, power, 1933, that, been, enlarged, reuse, large, stock, 47mm, ammunition, used, soviet, navy, equip,. The 45 mm anti aircraft gun 21 K was a Soviet design adapted from the 45 mm anti tank gun M1932 19 K This was a copy of a 3 7 cm 1 5 in German weapon designed by Rheinmetall that was sold to the Soviets before Hitler came to power in 1933 that had been enlarged to 45 mm 1 8 in to reuse a large stock of old 47mm ammunition It was used by the Soviet Navy to equip almost all of their ships from 1934 as its primary light anti aircraft gun until replaced by the fully automatic 37 mm 70 K gun from 1942 to 1943 It was used in World War II and during the Cold War as the Soviets exported their World War II era ships to their friends and allies However it was not very effective as its slow rate of fire and lack of a time fuze required a direct hit to damage targets 45 mm anti aircraft gun 21 K A 21 K on board the Krasny KavkazTypeAnti aircraft cannonPlace of originSoviet UnionService historyIn service1934 Used bySoviet UnionWarsSecond World War Cold WarProduction historyDesigned1932 34Produced1934 1947No built2799Variants40 K 41 KSpecificationsMass107 115 kilograms 236 254 lb Length2 3975 metres 7 866 ft Barrel length2 0725 metres 6 800 ft Shell45 386 mm SRShell weight1 065 2 14 kg 2 35 4 72 lb Caliber45 millimetres 1 8 in Actionsingle shotBreechsemi automatic vertical sliding blockElevationdepends on the mountTraverse360 Rate of fire25 30 rpm practical Muzzle velocity880 metres per second 2 900 ft s Effective firing range6 000 m 20 000 ft maximum ceiling Maximum firing range9 200 metres 10 100 yd at 45 Contents 1 Design 2 Description 2 1 Ammunition 3 See also 4 Notes 5 References 6 External linksDesign EditThe 46 caliber21 K was a minimal adaptation of the 53 K anti tank gun that was created by taking the latter s barrel and mounting it on a simple pedestal mount Its semi automatic breech automatically ejected the cartridge case and locked open ready for the next round This was less than ideal for an anti aircraft weapon that relied on its rate of fire to inflict damage on aircraft because every round had to be hand loaded 1 Fully automatic weapons of roughly this caliber like the 40 mm Bofors typically used 4 5 round clips of ammunition to produce rates of fire four times as high Early production guns had a built up barrel but later ones used a monobloc There were problems with the breech mechanism early in the production run and a number of the first year s production run lacked the semi automatic breech entirely 2 Description EditThe 21 K complete with its pedestal weighed 507 kg 1 118 lb It was manually operated and could elevate between 10 and 85 at a rate between 10 and 20 degrees per second It could traverse a full 360 at a rate between 10 and 18 degrees per second although this was practically limited by its actual location on ship In the mid 1930s special powered turrets were developed for use on river monitors The 40 K was a single gun turret that weighed 2 000 kg 4 400 lb and the 41 K was a twin gun turret that weighed 2 600 kg 5 700 lb Both turrets could elevate between 5 and 85 at a rate of 8 degrees per second and could traverse a full 360 at a rate between 4 8 and 9 8 degrees per second 2 Ammunition Edit The 21 K used the same ammunition as the 45 mm anti tank gun M1937 53 K The biggest problem in its role as an anti aircraft gun was that it wasn t provided with a time fuze that would detonate the shell at a specified distance from the gun This meant that only a direct hit would damage its target 2 Shell name Type Weight Filling Weight Muzzle velocityBR 240 armor piercing 1 42 kg 3 1 lb 18 g 0 63 oz 760 m s 2 500 ft s OT 033 Fragmentation tracer 1 065 kg 2 35 lb 52 g 1 8 oz 880 m s 2 900 ft s OR 73A Fragmentation tracer 1 41 kg 3 1 lb 37 g 1 3 oz 760 m s 2 500 ft s F 73 High explosive 1 41 kg 3 1 lb 74 g 2 6 oz 760 m s 2 500 ft s O 240 High explosive 2 14 kg 4 7 lb 118 g 4 2 oz 335 m s 1 100 ft s See also EditMain article 45 mm anti tank gun M1937 53 K Notes Edit Breyer p 275 a b c Russian 45 mm 46 1 77 21 K 13 May 2006 Retrieved 21 July 2009 References EditBreyer Siegfried 1992 Soviet Warship Development Volume 1 1917 1937 London Conway Maritime Press ISBN 0 85177 604 3 Campbell John 2002 Naval Weapons of World War Two London Conway Maritime Press ISBN 0 87021 459 4 Koll Christian 2009 Soviet Cannon A Comprehensive Study of Soviet Arms and Ammunition in Calibres 12 7mm to 57mm Austria Koll p 441 ISBN 978 3 200 01445 9 External links Edit nbsp Media related to 45mm 46 21 K gun at Wikimedia Commons K 21 on navweaps com Retrieved from https en wikipedia org w index php title 45 mm anti aircraft gun 21 K amp oldid 1072785883, wikipedia, wiki, book, books, library,
