T. STEECE. Rifling Ordnance, No. 37,924. Patented Mar. 17, 1863.

UNITED STATES PATENT OFFICE,

TECUMSEH STEECE, OF THE UNITED STATES NAVY. MPROVEMENT N R FLNG ORD NANCE.

Specification forming part of Letters Patent No. 37,924, dated March 17, 1863. To al., whon, it may concern : Beit known that I, TECUMSEH STEECE, of jectile fitting close within the bore, and hence the United States Navy, have invented a cer their whole expansive force will be employed tain new and useful Improvement in Cannon; to drive it forward. On reaching the rear end and I do hereby declare the following to be a of the grooves B, the projectile will have ac full and exact, description of the same, refer uired the necessary momentum and the gases ence being had to the accompanying drawings, will have expended much of their expansive making part of this specification, in which force. At this period the gases find an exit Figure 1 is a longitudinal section of a can through the grooves B, and in passing the shot non illustrating my invention at a ac, Fig. 4. impart a rotary motion thereto by acting upon Fig. 2 is a longitudinal section at y), Fig. 4. its oblique wings. The lands b, forming a Fig. 3 is a transverse section at a 2, Figs. I continuation of the bore A, so guide the shot and 2. Fig. 4 is a transverse section on a that its position and direction will be correct larger scale, taken on the same plane, but look when leaving the mnzzle of the gun. ing in an opposite direction. The invention is applicable not only to muz Similar letters of reference indicate corre zle-loading but equally so to breech-loading sponding parts in the several figures. guns of any form, either with or without an The subject of the said invention is a can enlarged breech-chamber. non adapted to impart rotation to a suitably The projectile employed may be of various formed projectile by the force of the gases forms, either fitting the bore through the chief escaping in the act of firing. art of its length or provided with latitudinal The invention particularly consists in so bands of soft metal, or a packing or sabot of forming the bore of the gun that a projectile any suitable form fitting the bore. The for of suitable size and form may be guided in its ward part of the projectile may be provided passage throughout the bore, fitting the latter with Wings or grooves adapted to maintain, with the least possible windage at the rear by the resistance of the atmosphere, the rota end, in order that it may receive the full ex tion initiated by the action of the escaping plosive force of the charge, but receiving ro gases upon the rear Wings, as before explained. tation immediately before leaving the gun by The said wings upon which the escaping gases the action of gases escaping through grooves act may be formed either upon the shot itself in the gun, as hereinafter explained. or upon a Sabot, which, after imparting its To enable others skilled in the art to which rotation to the shot, will be separated there my invention pertains to make and use the from after leaving the gun. I do not desire same, I will proceed to describe the nature of to be understood as limiting myself to any its construction and operation. specific form of projectile, but propose to use The cannon is first bored of an equal caliber any form which may be adapted to operate throughout. A number of longitudinal or scribed.with my improved gun, as hereinbefore de nearly longitudinal grooves, B, are then formed The invention may also be adapted for small near the muzzle, the bands b between the said arms as well as ordnance. grooves being a continuation of the main part The length of the grooves B relatively to A of the bore, and of equal internal diameter that of the whole bore may be varied as pref. there with. erence or experience may suggest. The projectile to be used with this cannon Having thus described my invention, what will be made for a part or the whole of its I claim therein as new, and desire to secure by length of a diameter to accurately fit the main Letters Patent, is part A of the bore, and provided at its rear A cannon or other fire-arm having at its end with oblique wings adapted to impart ro rear end a smooth cylindrical bore, A, and tation to the shot when acted upon by the es near its muzzle longitudinal or nearly longi caping gases. It will be apparent that on tudinal grooves, B, which constitute enlarge fire being communicated to the charge the ments in the bore, and are separated by lands resultant gases will be confined by the pro b, the ridges or inner surfaces of which lands

2 37,924 are in their radial distance from the center tudinally, to impart rotation to the projectile equal to the radius of the smooth portion A. by acting against oblique surfaces thereon, or of the bore, all as herein described, so as to on a sabot or casing to be used therewith. guide the projectile during its entire passage TECUMSEH STEECE. through the bore, confine the gases as much Witnesses: as possible until the projectile approaches the B. F. MONROE, muzzle, and then permit their escape longi- | F. J. HIGGINSON.