Mills bomb

Mills bomb is the popular name for a series of prominent British hand grenades. They were the first modern fragmentation grenades used by the British Army.

Overview

William Mills, a hand grenade designer from Sunderland, patented, developed and manufactured the "Mills bomb" at the Mills Munition Factory in Birmingham, England, in 1915. The Mills bomb was inspired by an earlier design by Belgian captain Leon Roland. Roland and Mills were later engaged in a patent lawsuit. The Mills bomb was adopted by the British Army as its standard hand grenade in 1915, and designated the No. 5.

The Mills bomb underwent numerous modifications. The No. 23 was a variant of the No. 5 with a rodded base plug which allowed it to be fired from a rifle. This concept evolved further with the No. 36, a variant with a detachable base plate to allow use with a rifle discharger cup. The final variation of the Mills bomb, the No. 36M, was specially designed and waterproofed with shellac for use initially in the hot climate of Mesopotamia in 1917, but remained in production for many years. By 1918 the No. 5 and No. 23 were declared obsolete and the No. 36 (but not the 36M) followed in 1932.