Shrapnel shell

Shrapnel shells were anti-personnel artillery munitions which carried a large number of individual bullets close to the target and then ejected them to allow them to continue along the shell's trajectory and strike the target individually. They relied almost entirely on the shell's velocity for their lethality. The munition has been obsolete since the end of World War I for anti-personnel use, when it was superseded by high-explosive shells for that role. The functioning and principles behind Shrapnel shells are fundamentally different from high-explosive shell fragmentation. Shrapnel is named after Major-General Henry Shrapnel (1761–1842), a British artillery officer, whose experiments, initially conducted in his own time and at his own expense, culminated in the design and development of a new type of artillery shell.

In 1784, Lieutenant Shrapnel of the Royal Artillery began developing an anti-personnel weapon. At the time artillery could use "canister shot" to defend themselves from infantry or cavalry attack, which involved loading a tin or canvas container filled with small iron or lead balls instead of the usual cannonball. When fired, the container burst open during passage through the bore or at the muzzle, giving the effect of an oversized shotgun shell. At ranges of up to 300 m canister shot was still highly lethal, though at this range the shots’ density was much lower, making a hit on a human target less likely. At longer ranges, solid shot or the common shell — a hollow cast-iron sphere filled with black powder — was used, although with more of a concussive than a fragmentation effect, as the pieces of the shell were very large and sparse in number.

Shrapnel's innovation was to combine the multi-projectile shotgun effect of canister shot, with a time fuze to open the canister and disperse the bullets it contained at some distance along the canister's trajectory from the gun. His shell was a hollow cast-iron sphere filled with a mixture of balls and powder, with a crude time fuze. If the fuze was set correctly then the shell would break open, either in front or above the intended target, releasing its contents (of musket balls). The shrapnel balls would carry on with the "remaining velocity" of the shell. In addition to a denser pattern of musket balls, the retained velocity could be higher as well, since the shrapnel shell as a whole would likely have a higher ballistic coefficient than the individual musket balls (see external ballistics).

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