Canister shot which is similar to case (or case-shot) is a kind of anti-personnel ammunition used in cannons. It was similar to the naval grapeshot, but fired smaller and more numerous balls, which did not have to punch through the wooden hull of a ship. Canister shot has been used since the advent of gunpowder-firing artillery in Western armies; however, canister (or case) shot saw particularly frequent use on land and at sea in the various wars of the 18th and 19th century. The canister round is similar to a case (hence the confusion between case shot and canister shot) and is still used today in modern artillery, particularly in the main armament of tanks with smoothbore cannons.
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