Projectile with fire-safe infra-red strike point marking

Abstract

A projectile ( 100, 100 a, 100 b, 100 c ) containing two chemiluminescent dye components ( 123, 125 ), a dye powder ( 126 ) and one or more capsules ( 170 ) containing a pyrophoric substance. Upon impact at a target, a nose cap ( 110 ) of the projectile ( 100, 100 a, 100 b, 100 c ) and the capsule(s) ( 170 ) become broken, thereby allowing the pyrophoric substance to oxidize and emit an infra-red signal to mark the strike point. Oxidation of the pyrophoric substance is controlled, to allow the projectile to be fire-safe.

1 . A projectile having an elongate body, which defines a longitudinal axis, with a front portion being connectable to a hollow nose cap and a rear portion connectable to a cartridge case, the projectile comprising:
 an ampoule disposed inside the hollow nose cap, with the ampoule's longitudinal axis substantially coaxial with the longitudinal axis of the projectile, and the ampoule containing a first luminescent dye component;   a vial disposed inside the ampoule, with the vial containing a second luminescent dye component;   a dye powder filing a cavity between the hollow nose cap, the ampoule and the front portion of the projectile body; and   one or more capsules containing a pyrophoric substance, with the one or more capsules being disposed in the dye powder and at the front portion of the projectile body;   wherein, upon the projectile striking a target, the nose cap and the one or more capsules become broken, thereby allowing the pyrophoric substance to oxidize and to emit an infrared signal to mark the point of impact.   
     
     
         2 . The projectile according to  claim 1 , further comprising a support ring to maintain the one or more capsules at the front end of the projectile body. 
     
     
         3 . The projectile according to  claim 2 , further comprising a shield disposed between the one or more capsules and the ampoule. 
     
     
         4 . The projectile according to  claim 2 , wherein the support ring and the shield are made of paper. 
     
     
         5 . The projectile according to  claim 4 , wherein the support ring and shield are mortised or glued together. 
     
     
         6 . The projectile according to  claim 4 , wherein the support ring and shield are integrally formed in one piece by corrugations. 
     
     
         7 . The projectile according to  claim 4 , wherein the shield is cylindrical and the support ring is constituted by flaps folded out from one end of the cylindrical shield. 
     
     
         8 . A method of marking a strike point of a projectile with an infra-red signature, the method comprising:
 breaking a nose cap on a projectile and one or more capsules containing a pyrophoric substance by impact forces after the projectile strikes a target or ground, and allowing the pyrophoric substance to oxidize for a short duration of time so that the infra-red signature is detectable by a thermal camera, yet keeping the broken projectile fire-safe.   
     
     
         9 . A use of an infra-red emitter using a pyrophoric substance having a short burn duration in a fire-safe projectile.