The gun was based on the barrel of the QF 4-inch Mk V and the breech mechanism of the BL 4-inch Mk VIII[4] and was first introduced in World War I on capital ships as secondary armament in triple-gun mountings, intended to provide rapid concentrated fire.

They are not mounted in one sleeve; have separate breech mechanism, a gun crew of 23 to each triple".

[5] Guns were thereafter used in single-gun mountings, typically on smaller ships as the main armament.

In World War II, the gun was employed on many small warships such as Flower-class corvettes and minesweepers, primarily for action against surfaced submarines.

It was succeeded on new small warships built in World War II by the QF 4-inch Mk XIX gun which fired a slightly heavier shell at much lower velocity and had a high-angle mounting which added anti-aircraft capability.