Spherical Case-Shot

A spherical case-shot consists of a thin shell of cast iron, containing a number of musket-balls, and a charge of powder sufficient to burst it; a fuze is fixed to it as in an ordinary shell, by which the charge is ignited and the shell burst at any particular instant. A spherical case-shot, when loaded ready for use, has about the same specific gravity as a solid shot, and therefore, when fixed with the service charge of powder, its range, and its velocity at any point in its range, is about equal to that of a solid shot of the same caliber. The spherical case mostly used for field service is the 12-pounder, and contains, when loaded, 90 bullets. Its bursting charge is 1 ounce of powder, and it weighs 11.75 pounds. Its rupture may be made to take place at any point in its flight, and it is therefore superior to grape or canister. The attrition of the balls with which it is loaded, formerly endangered the firing of the bursting charge. This is now obviated, in making one ma of the balls, by pouring in melted sulphur. It is also prevented by Capt. Boxer’s improved spherical case-shot, of which there are two forms. In one form the bursting charge of powder is contained in a cylindrical tin box, attached to a bra socket which receives the fuze, and which is screwed into the shell. In the other, the part of the shell containing the bursting charge is separated from that containing the bullets by a diaphragm of sheet-iron, cast into the shell ( i.e. , the shell is cast on to the diaphragm which is inserted into the core). The bullets are introduced into the shell by a second orifice, and are kept in their places by a composition afterwards poured in. The present 12-pounder spherical case-shot, fixed with a charge of 2 1 ⁄ 2 pounds of powder, is effective at 1500 yards. The proper position of the point of rupture varies from 50 to 130 yards in front of, and from 15 to 20 feet above, the object. The mean number of destructive pieces from a 12-pounder spherical case-shot, which may strike a target 9 feet high and 54 feet long, at a distance of 800 yards, is 30. The spherical case-shot from rifle-cannon is said to be effective at over 2000 yards. Spherical case should not be used at a le distance than 500 yards.