GB681916A - Improvements in or relating to ammunition projectiles - Google Patents

Abstract

681,916. Ammunition projectiles. ANSTALT FUR DIE ENTWICKLUNG VON ERFINDUNGEN UND GEWERBLICHEN ANWENDUNGEN ENERGA. Jan. 10, 1950 [Jan. 17, 1949], No. 599/50. Classes 9(i) and 9(ii) A rocket projectile having a nose fuze 1, a casing 2 containing the explosive charge, and a tail part 3 comprising a tubular propellant chamber carrying stabilizing blades 4, 5 has the blades arranged in pairs symmetrically grouped round the tail, the members of each pair being mutually inclined and symetrically placed with respect to the longitudinal axis of the projectile. For velocities between 100 and 300 ms./sec. the angle between the members of each pair is between 2 and 10 degrees. In each pair of blades the blade 4 which is inclined in the direction of rotation has a greater height than the blade 5. The propellant gases escape through nozzles 7 after rupturing membranes 8. Each nozzle has a milled recess 9 whereby the escaping gases cause the projectile to rotate as described in Specification 681,977. The tail part 6 carrying the nozzles may be of aluminium and each membrane 8 is held on its seating by a collar 10 of heat-resistant material, e.g. steel. On firing from a projector the striker hits a primer cap 11 fixed in a carrier 12 to initiate an ignition charge 13 which in turn ignites an aluminothermic charge 13a in an axially arranged tube 14, Fig. 4. The charge 13a ignites the propellant 15 through apertures in the tube. The propellant is in the form of hollow sticks arranged 'symmetrically about the tube 14 and resting on an annular grid 16 with a vaulted cross-section as described in Specification 681,978. Lateral openings 17 in the grid allow the gases to escape while retaining unburnt particles of powder. The forward end of the propellant chamber is screwed to a coupling 18 which is itself screwed to the body of the projectile. The propellant chamber has a forward extension 21 to prevent excessive rise' in internal pressure, a ring 22 holding the sticks 15 in position (Fig. 6). The blades 4, 5 may be a single unit either forced on to the tail or secured by glue or held by the nozzle carrier 6 (Fig. 7). An auxiliary striker 23 in the form of a valve protected by a membrane 24 may be used to actuate the primer 11 and prevent rearward ejection of gases from the charge 13. The 'nozzle carrier 6 may be formed as a single unit with the blades 4, 5. The nozzles may be grouped in pairs or threes and some nozzles may have membranes collapsing when the internal pressure exceeds the safety limit. The propellant chamber may be lined with heat-insulating material 25, e.g. cardboard sheet and have an external coating decreasing heat-absorption; e.g. white paint.