Mörser Karl - 600mm German Mortar (History)

The self-propelled version of the 60cm siege mortar was ordered in June 1937. General Karl Becker of the Artillery was involved in the development, hence the name Karl was used to describe the gun. The driving trials were held at Unterlüss in May 1940. Delivery of the six production vehicles took place from November 1940 to August 1941. In February 1941, discussions commenced, concerning increasing the range of the weapon, and in May 1942, 54cm barrels (Gerät 041) were ordered for the six vehicles. At a conference with Hitler in March 1943, it was stated that the first 54cm Gerät 041 would be delivered by June 1943, and the third, by mid-August. The 60cm and 54cm barrels appear to have been interchanged as required. In 1945, US forces captured vehicle II with a 60cm, and vehicle V with a 54cm.


The prototype chassis, built in 1939, had eight road wheels with external swing arms. Production Karl had eleven road wheels. Ammunition was transported in a tracked Munitionsschlepper converted from the PzKpfw IV, four rounds in each Schlepper. For the 60cm 040, the s Be Granate weighed 2.117 tons and the Ie Be Granate, 1.70 tons; in this case of the 54cm Gerät 041, 1.58 tons and 1.25 tons respectively. Maximum rate of the fire was 6 rph (rounds per hour).

Guns I-IV went to the Russian Front in July 1941 with the 628th schwere Artillerie Abteilung. They saw action at various sites, including Lemburg in that year. The best known action was against Sevastopol in 1942. Later, four guns were issued to the 833rd schwere Artillerie Abteilung (mot). These guns had the names Adam, Eve (1st Batt.) and Thor, Odin (2nd Batt.) The names for guns V and VI were Loki and Ziu.

The fully tracked self-propelled carriage moves into position, Russia 1941 (seen here from the rear) It had a ground pressure of only 1.7 kilograms per square centimeter (Kg/cm2).

The carriage has already sunk down onto it eleven return rollers and the ammunition carrier has pulled alongside - within ten minutes the mortar will be ready for firing.

Right side of the "Ziu" mortar. The crew is adjusting the mortar's barrel to its maximum elevation of 70°. The upper carriage has a double return for the barrel and the carriage, which have a respective movement of 92cm and 78cm. The four barrel recoil braking mechanisms develop a braking pressure of 580 t : the two braking mechanisms for the carriage build a pressure of 104 t. The barrel and the carriage each have two counter-recoil mechanism, which pressure increases from 60 at. to 138 at.

With an opened flat wedge breech the electrically driven mechanical loader pushes the shell into the massive barrel, dropped into its horizontal loading position. Notice the extremely thick base plate, which must withstand gas pressure of 1800 at. and a muzzle energy of up to 6950 m/t.

The 1.991 meter long, 1.70 metric ton, 60cm leichte Betongranate 040.

The 2.511 meter long, 2.17 metric ton, 60cm Schwere Betongranate 040.

The loading tray with rammer was mounted onto rear of the gun carriage. Due to the difference in diameter, the loading tray for 60cm shells couldn't be used for 54cm shells.

A redesigned suspension having 11 steel-tired road wheels per side was introduced with Gerät.

Cutaway profile of the Karl Gerät 040 lowered into firing position. A large gap was left between the carriage and the engine compartment (Maschinenraum at the front of the vehicle) so that the entire carriage could recoil.