4-inch Naval Gun and Mounting This weapon, and its mounting, are
late-war developments of the main gun carried by Canadian
corvettes and other escort ships. The original design of this
gun dated to the First World War. While effective against
surfaced submarines and capable of firing starshells to provide
night-time illumination, it proved relatively slow to operate
and offered little protection to its crew. This modified
version, developed too late to see service during the Second
World War, could fire shells faster and farther. An improved gun
shield offered better protection to its crew. Gun, Naval,
4-inch, Quick-firing, Mk XXI Mount, Naval, 4-inch, Mark XXIV