The largest gun ever used in combat is the German "Gustave Gun" or "Schwerer Gustave" .
The Gustave Gun was built in 1941 by the Krupp Company . It had an 80 cm bore and fired either 10500 lbs HE projectile ( which could make a crater 30 ft wide and 30 ft deep ) or a 16500 lbs concrete piecing projectile (which would penetrate 264 feet of reinforced concrete.
The typical powder charge was about 3000 lbs of powder . And its range can reach 23 to 29 miles.
The gun weighed 1344 tons and had a crew of 500 men!!
Tgis gun was used in the Germans during tge seige at Sevestapol in April 1942.
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