The Berezin B-20 (Березин Б-20) was a 20 mm caliber autocannon used by Soviet aircraft in World War II.

B-20
Second from the top in the middle
TypeAutocannon
Place of originUSSR
Service history
In serviceSoviet Air Forces, Soviet Air Defence Forces
WarsWorld War II, Korean War
Production history
DesignerMikhail Yevgenyevich Berezin
Designed1944
Specifications
Mass25 kg (55 lb)
Length2,035 mm (80.1 in)
Barrel length1,588 mm (62.5 in)

Cartridge20×99mm
Caliber20 mm (0.8 in)
Barrels1
ActionGas
Rate of fire800 rounds/min (600 synchronized)
Muzzle velocity790–815 m/s (2,590–2,670 ft/s)

Development edit

The B-20 was created by Mikhail Yevgenyevich Berezin in 1944 by converting his 12.7 mm Berezin UB machine gun to use the 20 mm rounds used by the ShVAK cannon. No other changes were made to the weapon which was pneumatically or mechanically charged and was available in both synchronized and unsynchronized versions. In 1946, an electrically-fired version was created for the turrets of the Tupolev Tu-4 bomber until the Nudelman-Rikhter NR-23 cannon became available. The B-20 was a welcome replacement for the ShVAK because it was significantly lighter - 25 kg (55 lb) to the 40 kg (80 lb) ShVAK - without sacrificing rate of fire or muzzle velocity.

Specifications edit

  • Ammunition: 20×99mm
  • Empty weight: 25 kg (55 lb)
  • Muzzle velocity: 750–770 m/s (2,460-2,525 ft/s)
  • Rate of fire: 800 rounds/min
  • Mass of one-second burst: 0.95 kg (2.1 lb)

Production edit

The Soviet archives register the following production numbers by year:[1]

  • 1944 — 2,275
  • 1945 — 7,240
  • 1946 — 440
  • 1947 — 780
  • 1948 — 1,686
  • 1949 — 2,931

See also edit

Related developments:

Similar weapons:

Notes edit

  1. ^ Shirokograd, p 119

References edit

  • Широкоград А.Б. (2001) История авиационного вооружения Харвест (Shirokograd A.B. (2001) Istorya aviatsionnogo vooruzhenia Harvest. ISBN 985-433-695-6) (History of aircraft armament)
  • Koll, Christian (2009). Soviet Cannon - A Comprehensive Study of Soviet Arms and Ammunition in Calibres 12.7mm to 57mm. Austria: Koll. p. 121. ISBN 978-3-200-01445-9.