Ammunition comes in a great range of sizes and types, often designed to work only in specific weapons. It’s purpose is to project a force against a selected target to have an effect.
However, there are international standards for certain types that enable their use across different weapons. Small arms and light weapons ammunition includes a wide variety of products. They are used in a variety of firearms ranging from pistols to rifles and shot guns to heavier automatic weapons sometimes called machine guns. There are also specific sizes of it that are designed to have a specialized effect on a target. In general, projectiles less than 20 mm or .60 inch in diameter are classified as small arm.