914mm Little David

HISTORY - Combat Testing The Largest Mortar Ever - 914mm Little David 
 
Little David was the nickname of an American 36-inch (910 mm) caliber mortar used for test firing aerial bombs during World War II, that is one of the largest calibre guns ever built, having a larger calibre than both of Germany's Dora and Gustav which were 31.5-inch (800 mm) railway guns. 

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