The heavy self propelled assault gun sturmpanzer Bär ( bear)
Early May of 1942, a new design of Sturmpanzer, was proposed. On March 4th of 1943, Krupp proposed development of new Sturmgun armed with 305mm L/16 mortar and first drawings were ready in May. It was to be armed with a 305mm gun mounted in the superstructure, based on the modified chassis of the then new Panzerkampfwagen VI Tiger (Tiger I) heavy tank utilized some Panther components with new suspension developed by Krupp. The new vehicle was to weight 120 tons.
This new Sturmpanzer was to be powered by a 12-cylinder Maybach HL 230 P 30 engine producing 700hp. This would have al-lowed the vehicle to travel at a maximum speed of approximately 20km/h [12 mph]. Bär was to be armed with a rigidly-mounted 305mm KwK L/16 gun installed in an armored superstructure in the back of the hull. The main gun could only be elevated from 0 to 70 degrees and had a range of 10,500 meters [11,400 yards]. Each 305mm round weighed 350kg [770 pounds] and carried a 50kg [110 pound] charge. The interior storage space allowed for only 10 rounds.
Another weapon proposed was the 210mm L/21 wich this panzer should be contain 22 proyectiles.
It was to be 8.2 meters [26.7 feet] long, 4.1 meters [13.65 feet] wide and 3.5 meters [11.4 feet] high. Armor was sloped and protection ranged from 80mm on the sides to 130mm at the front. Sturmpanzer Bär was to be operated by a crew of six - commander, gunner, two loaders, driver and radio-operator. The project never left the drawing board, but was a step in the development of the Sturmtiger.