QF 4-inch naval gun Mk IV, XII, XXII
The QF 4-inch gun Mk IV[note 1] was the main gun on most Royal Navy and British Empire destroyers in World War I.
Mk IV armed many British destroyers and some cruisers in World War I.
It was used to arm merchant ships in World War II.
These submarine guns fired a heavier 35 pounds (16 kg) projectile from late 1944.
[2] Shortly after the end of hostilities, the Mk XXII was superseded in new British submarines by the lighter QF 4 inch Mk XXIII.
On
R-class destroyer
HMS
Satyr
c.
1917–1918
Gun recoiling after firing, on Australian auxiliary anti-submarine vessel
HMAS
Wilcannia
c.
1943
