The 15 cm sIG 33 was a 150mm infantry gun used by the German Army in World War II. It was in service between 1927 and 1945 and was deployed in every military campaign of the war. Fitted with a hydro-pneumatic recoil system, it was a good accurate gun used to soften up the ground and wipe out enemy machine gun nests and bunkers before an infantry attack. The only drawback was its weight; it was too heavy and had to be towed by a team of four or six horses to the battlefield as it was mounted on a two-wheeled box-trail carriage. It fired three types of ammunition: high explosive, shaped-charge, and demolition shells; the latter one was a finned 90-kg shell, fired with a driving rod and used against concrete structures. With a rate of fire of up to 4 rounds per minute, this infantry gun had a maximum range of 7 km. Rheinmetall produced more than 4,500 15 cm sIG 33 guns. It was also employed by the German Artillery but mounted on the Panzer I light tank chassis and was designated sIG 33 auf Geschützwagen I, II, or III, which was a self-propelled artillery piece.
Caliber: 150 mm
Weight: 1,800 kg
Barrel length: 1.6 m
Breech: horizontal sliding block
Muzzle velocity: 240 m/s