Field artillery in the American Civil War
Canister Shot – Like spherical case it is a shrapnel round used against enemy troop formations. It contains usually between 20 and 30 large solid round balls. When fired it spreads out in a cone shape from the muzzle like a large shotgun blast. When canister balls were scarce, nails, scrap iron or other materials were used. Canister was a short range weapon usually effective at up to . Some artillery commanders used a technique of firing canister at the ground in front of advancing troops. The effect was to bounce the canister shot into the formation and cause more deaths.