3 cm MK 303 Flak

The 3 cm MK 303 Flak and twin-mounted 3 cm MK 303 Flakzwilling (M44) were experimental 30 mm anti-aircraft guns developed in Nazi Germany. They fired the powerful 30x210mm round and only 222 were produced.[1] The gun was to be installed on Type XXI submarines as AA defense[3] and its use as AA defense replacing 2 cm Flak and 3.7 cm Flak weapons was also considered. The use of 3 cm M.K. 303 Flakzwilling on Flakpanzer IV "Kugelblitz" was considered, but rejected. The development began in late 1941[1] and production started in late 1944.

3 cm MK 303 (Br)
3 cm flak 303 twin ubts.jpg
3cm MK 303 Flakzwilling, two 3 cm MK 303 in the twin mount
TypeAnti-aircraft cannon
Place of originNazi Germany
Service history
In serviceunknown
Used byNazi Germany
WarsWorld War II
Production history
No. built222 (32 in 1944 and 190 in 1945)[1]
Variants3 cm Flakzwilling MK 303 (Br)
Mass185 kg (408 lbs)[2]
Length3.145 m (10 ft 3.8 in)
Barrel length2.2 m (7 ft 3 in) L/73

Caliber30 mm (1.18 in)
Elevation-10°to ±85°
Rate of fire400 rpm (cyclic)
Muzzle velocity1100 m/s (3,609 ft/s) M-Schos
900 m/s (2,953 ft/s) HE
950 m/s (3,117 ft/s) AP/HE[2]
Feed system15 cartridge clip

Post War UsageEdit

Postwar PLDvK vz. 53
of Czechoslovak army

In the 50s, the MK 303 was produced in Czechoslovakia under the designation M53, with the clip feed replaced by a 10-round box magazine.[1] It was also used as armament of SPAAG M53/59 Praga.


  1. ^ a b c d e "Авиапушки Кригхоффа. MG 301, MK 303". December 28, 2015.
  2. ^ a b "3 cm M.K.303 (Br) / 3 cm Flakzwilling M.K.303 (Br) : Germany (DEU)". armedconflicts.com.
  3. ^ "dsub geschütze". www.ww2technik.de.