The howitzer as an anti-submarine weapon was handicapped by the comparatively small weight of the bursting charge of its shell.

This applied more particularly to the earlier patterns, and to inflict fatal injury it was necessary to burst the shell in close proximity to the submerged submarine.

This weapon, although not very popular at first, soon, however, proved its value, when employed both from patrol craft and from merchant ships.
One curious instance occurred on March 28, 1918, of a merchant ship being saved by a 7.5-inch howitzer.

A torpedo was seen approaching at a distance of some 600 yards, and it appeared certain to hit the ship.

A projectile fired from the howitzer exploded under water close to the torpedo, deflected it from its course, and caused it to come to the surface some 60 yards from the ship; a second projectile caused it to stop, and apparently damaged the torpedo, which when picked up by an escorting vessel was found to be minus its head.
Delivery of howitzers commenced in June, 1917, and continued as follows: Total completed, No.