B-20
OriginUSSR
Is rangedy
ServiceSoviet Air Forces, Soviet Air Defence Forces
WarsWorld War II, Korean War
DesignerMikhail Yevgenyevich Berezin
Design date1944
Weight25 kg (55 lb)
Length2,035 mm (80.1 in)
Part length1,588 mm (62.5 in)
Cartridge20×99mmR
Caliber20 mm (0.8 in)
Barrels1
ActionGas
Rate800 rounds/min (600 synchronized)
Velocity790–815 m/s (2,600–2,670 ft/s)

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

Development

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

  • Ammunition: 20×99mm
  • Empty weight: 25 kg (55 lbs)
  • Muzzle velocity: 750–770 m/s (2,460-2,525 ft/s)
  • Rate of fire: 800 rounds/min (600 synchronized)
  • One-second burst-mass: Unsynchronized, 1.27 kg (2.8 lbs); Synchronized, 0.95 kg (2.1 lbs)

Production

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

Related developments:

Similar weapons:

Notes

  1. ^ Shirokograd, p 119

References