15cm sIG33 auf Panzer II
The Bison has a 15cm sIG33 (L/12) infantry gun mounted on a highly modified Panzer II chassis. The Panzer II chassis was both widened, lengthened and an extra roadwheel added. The destructive power of the 15cm round of the sIG 33 was greatly appreciated, but due to the short range and poor mobility of the towed gun, it rarely got into action during attacks. The first self-propelled version was the 15cm sIG 33 (Sfl) auf Pz.Kpfw I and saw combat in May 1940. But development had already begun on an improved model based on the Panzer II chassis. On the first test variant, the howitzer was mounted on its wheeled carriage, but proved too far to the rear and firing it resulted in the vehicle tipping backwards from the recoil. Without its wheels the sIG 33 could be mounted further forward, a significant advantage for stability when firing. The room inside a standard Panzer II was small, so a lengthened and widened hull was made. Additional space in the fighting compartment was also achieved by mounting the engine transversely across the rear of the vehicle. Unlike the normal Panzer II suspension, a sixth road wheel was added to the lengthened chassis. These vehicles were organized into two independent companies and were sent to the Afrikakorps, in Libya, to take part in the intended attack on Tobruk. These were the 707. and 708. sIG Kompanie (mot S). The Bisons were engaged in the major offensive called Operation Venezia, the initial attack on the Gazala line. Combat experience quickly revealed the engine’s weakness and many other design faults, mostly aggravated by African climatic conditions, under strain the overloaded vehicle would overheat.
Weight: 12 tons
Armour Thickness: 30mm - hull front, 14.5mm - gun shield
Armament: one 15cm S.I.G. 33, one 7.92mm MG-34 machine gun
Range: 100km on roads