MK 103 cannon
Encyclopedia
The Rheinmetall-Borsig
MK 103 was a German
30 mm caliber
autocannon
that was mounted in German combat aircraft during World War II
. Intended to be a dual purpose weapon for anti-tank and air-to-air fighting, it was a development of the heavy MK 101
. Compared to the MK 101, it was lighter, faster-firing, and was originally intended to develop a higher muzzle velocity than the MK 101. Unlike the MK 101, the MK 103 used a belt feed, allowing it to potentially carry a larger ammunition load. The MK 103 used electrically primed rather than percussion primed ammunition. The firing mechanism differed from the recoil operated MK 101 in that it used a combination of gas and recoil operation. After firing, gas pressure serves to unlock the breech, while barrel recoil was used to cycle the action (eject spent cartridge and load a fresh one).
However, through a combination of lower grade steels and lighter components, the mechanism was not as strong as the MK 101. To counteract this weakness HE ammunition used a reduced load of propellant, resulting in a lowered muzzle velocity (-100 m/s) compared to the MK 101. The rate of fire was also reduced as a result, though still superior to that of the MK 101. The Armour-piercing 30 mm cartridge retained a full propellant charge, as the resulting higher muzzle velocities were felt to be worth the risk. The MK 103 entered service in 1943 as main armament of the Hs 129 B-1
ground-attack/tank-destroyer aircraft, mounted below the central fuselage in a conformal gun pod
.
The original specification for the weapon called for it to fit inside the engine mounting (possibly as a Motorkanone, firing through a hollow propeller hub) of aircraft, however the final weapon was too large and heavy to fit into small-size fighters like the Bf 109
. Unless mounted on the aircraft's centerline, the asymmetric shock from the cannon's recoil tended to veer the aircraft off course. The only known usage of the original MK 103 in a Motorkanone fitment was in the Do 335
. A modified version with a reduced-profile barrel - the MK 103M - was developed and possibly tested for possible use as a Motorkanone cannon on single-engine fighter planes such as the Bf-109K, but probably never saw active service. As a consequence, the MK 103 was largely restricted to the role of an air-to-ground weapon for use against armoured vehicles.
A limited-production series of the Fw 190A
fighter and Fw 190F ground attack fighter (which utilized a particularly strong wing/fuselage design) incorporated two MK 103 cannons, one apiece mounted in a gondola under each wing. Later in the war the MK 103 was also used as a ground-based anti-aircraft (AA) weapon, using single or dual mounts. It was also used in the Flakpanzer IV "Kugelblitz"
.
Developed alongside the MK 103 was a lighter short-ranged MK 108 cannon
which fired the same projectiles using a smaller cartridge case with less propellant.
Rheinmetall
Rheinmetall AG is a German automotive and defence company with factories in Düsseldorf, Kassel and Unterlüß. The company has a long tradition of making guns and artillery pieces...
MK 103 was a German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
30 mm caliber
30 mm caliber
30 mm caliber ammunition is usually used in autocannon. Such ammunition includes NATO standard 30 × 173 mm and 30 × 113 mm and Soviet 30 × 165 mm ammunition widely used around the world....
autocannon
Autocannon
An autocannon or automatic cannon is a rapid-fire projectile weapon firing a shell as opposed to the bullet fired by a machine gun. Autocannons often have a larger caliber than a machine gun . Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded for a...
that was mounted in German combat aircraft during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. Intended to be a dual purpose weapon for anti-tank and air-to-air fighting, it was a development of the heavy MK 101
MK 101 cannon
The MK 101 is the designation of a 30 mm autocannon used in German combat aircraft during World War II. Although accurate and powerful, with a high muzzle velocity, it was very heavy, with a low rate of fire, which limited its production....
. Compared to the MK 101, it was lighter, faster-firing, and was originally intended to develop a higher muzzle velocity than the MK 101. Unlike the MK 101, the MK 103 used a belt feed, allowing it to potentially carry a larger ammunition load. The MK 103 used electrically primed rather than percussion primed ammunition. The firing mechanism differed from the recoil operated MK 101 in that it used a combination of gas and recoil operation. After firing, gas pressure serves to unlock the breech, while barrel recoil was used to cycle the action (eject spent cartridge and load a fresh one).
However, through a combination of lower grade steels and lighter components, the mechanism was not as strong as the MK 101. To counteract this weakness HE ammunition used a reduced load of propellant, resulting in a lowered muzzle velocity (-100 m/s) compared to the MK 101. The rate of fire was also reduced as a result, though still superior to that of the MK 101. The Armour-piercing 30 mm cartridge retained a full propellant charge, as the resulting higher muzzle velocities were felt to be worth the risk. The MK 103 entered service in 1943 as main armament of the Hs 129 B-1
Henschel Hs 129
The Henschel Hs 129 was a World War II ground-attack aircraft fielded by the German Luftwaffe. Its nickname, the Panzerknacker , is a deliberate pun—in German, it also means "safe cracker"...
ground-attack/tank-destroyer aircraft, mounted below the central fuselage in a conformal gun pod
Gun pod
A gun pod is a detachable pod or pack containing machine guns or automatic cannon and ancillaries, mounted externally on a vehicle such as a military aircraft which may or may not also have its own guns....
.
The original specification for the weapon called for it to fit inside the engine mounting (possibly as a Motorkanone, firing through a hollow propeller hub) of aircraft, however the final weapon was too large and heavy to fit into small-size fighters like the Bf 109
Messerschmitt Bf 109
The Messerschmitt Bf 109, often called Me 109, was a German World War II fighter aircraft designed by Willy Messerschmitt and Robert Lusser during the early to mid 1930s...
. Unless mounted on the aircraft's centerline, the asymmetric shock from the cannon's recoil tended to veer the aircraft off course. The only known usage of the original MK 103 in a Motorkanone fitment was in the Do 335
Dornier Do 335
The Dornier Do 335 Pfeil was a World War II heavy fighter built by the Dornier company. The two-seater trainer version was also called Ameisenbär . The Pfeils performance was much better than other twin-engine designs due to its unique "push-pull" layout and the much lower drag of the in-line...
. A modified version with a reduced-profile barrel - the MK 103M - was developed and possibly tested for possible use as a Motorkanone cannon on single-engine fighter planes such as the Bf-109K, but probably never saw active service. As a consequence, the MK 103 was largely restricted to the role of an air-to-ground weapon for use against armoured vehicles.
A limited-production series of the Fw 190A
Focke-Wulf Fw 190
The Focke-Wulf Fw 190 Würger was a German Second World War single-seat, single-engine fighter aircraft designed by Kurt Tank in the late 1930s. Powered by a radial engine, the 190 had ample power and was able to lift larger loads than its well-known counterpart, the Messerschmitt Bf 109...
fighter and Fw 190F ground attack fighter (which utilized a particularly strong wing/fuselage design) incorporated two MK 103 cannons, one apiece mounted in a gondola under each wing. Later in the war the MK 103 was also used as a ground-based anti-aircraft (AA) weapon, using single or dual mounts. It was also used in the Flakpanzer IV "Kugelblitz"
Kugelblitz
The Flakpanzer IV Kugelblitz was a German self-propelled anti-aircraft gun developed during World War II. By the end of the war, only a pilot production of five units had been completed...
.
Developed alongside the MK 103 was a lighter short-ranged MK 108 cannon
MK 108 cannon
The MK 108 was a 30 mm caliber autocannon manufactured in Germany during World War II by Rheinmetall-Borsig for use in aircraft.-Development:...
which fired the same projectiles using a smaller cartridge case with less propellant.
Specifications
- Type: single-barrel automatic cannon
- Caliber: 30x184B
- Operation:
- Length: 2,335 mm (91.9 in) (with muzzle brake)
- Barrel length: 1,200 mm (47.2 in) (incl. muzzle brake)
- Rifling angle:
- Weight: 145 kg (320 lb)
- Weight (complete):
- Cartridge weight: 800 g (28.22 oz) (M-Geschoss)
- Projectile weight: 330 g (11.64 oz) (M-Geschoss)
- Muzzle velocity: 860 (HE/M) to 960 (AP-T) m/s (2,822 to 3,150 ft/s)
- Armour penetration: AP-T(WC) 70 mm (2.75 in)/60°/300 m (656 ft) or 100 mm (3.9 in)/90°/300 m (656 ft)
- Rate of fire: 380 (HE/M) to 420 (AP) rounds/min