The 5-Inch/54-caliber (Mk 45) lightweight gun is a modern U.S. naval artillery gun mount consisting of a 5-inch (127 mm) L54 Mark 19 gun on the Mark 45 mount. It is designed to be used against surface warships, for anti-aircraft use and shore bombardment to support amphibious operations.
The gun mount features an automatic loader with a capacity of 20 rounds. These can be fired under full automatic control, taking a little over a minute to exhaust those rounds at maximum fire rate. For sustained use, the gun mount would be occupied (below deck) by a three-man crew (gun captain, panel operator, and ammunition loader) to keep the gun supplied with ammunition. #caliber_Mark_45_gun #cannon #navy