Ammunition and weapon system

Abstract

This ammunition and weapon system, in which a projectile ( 7 ) is thrust by a propellant gas obtained from the combustion of a propellant charge ( 10 ) inside a barrel ( 4 ) that is closed at one end by a breech ( 1 ) and is open at its other end, is characterized that at least part of the propulsion gases generated by the combustion of the propellant charge ( 10 ) runs through a nozzle ( 3 ) which is located in the barrel ( 4 ), between the breech ( 1 ) and the projectile ( 7 ), and which comprises a convergent ( 3 a ), a neck ( 3 b ) and a divergent ( 3 c ), one after the other in the direction of the open end of the barrel.

1 . An ammunition and weapon system, wherein a projectile is thrust by a propellant gas coming from the combustion of a propellant charge inside a barrel closed at one end by a breech and open at the other end thereof, wherein at least a part of the propulsion gases generated by the combustion of the propellant charge passes through a nozzle bringing the propulsion gases to a supersonic speed, placed in the barrel, between the breech and the projectile, and including a converging portion, a throat and a diverging portion, one after the other toward the open end of the barrel. 
     
     
         2 . The system according to  claim 1 , wherein the nozzle is formed inside a chamber which is removable from the barrel so as to make possible the loading of the propellant charge by the rear end and the loading of the projectile by the front end of the chamber. 
     
     
         3 . The system according to  claim 1 , wherein the nozzle is formed inside a cartridge case forming an ammunition grouping the projectile and the propellant charge before firing. 
     
     
         4 . The system according to  claim 2 , wherein the projectile is positioned relative to the barrel before the firing by matching between the shape of a base of the projectile or of one or a plurality of sabots and a portion of the nozzle. 
     
     
         5 . The system according to  claim 1 , wherein the propellant charge comprises a priming composition, a fast-burning charge and a slow-burning charge. 
     
     
         6 . The system according to  claim 1 , wherein at least one portion of the barrel has a conical cross-section and in that the projectile is associated with at least one sabot degradable during the displacement thereof in the conical cross-section portion of the barrel. 
     
     
         7 . The system according to  claim 6 , wherein the sabot is made of a material deposited on the barrel as same moves therethrough, in order to form a thermal protection layer of the latter which is then discharged. 
     
     
         8 . The system according to  claim 7 , wherein the discharge of the protective layer from the barrel is obtained:
 either by a change of phase, i.e. liquefaction, evaporation or sublimation, of the material forming the sabot, or   same may result from a reaction of the material forming the sabot with the propellant gases from the combustion of the propellant charge,   either self-burning of the material of the sabot, or   a combination of at least two of the three methods described.   
     
     
         9 . The system according to  claim 6 , wherein the sabot is composed of at least one of the following materials: nitrocellulose, nitroglycerin, shellac, gum arabic, gum tragacanth, gelatin, dextrin, asphalt, polybutadienes, polyesters, polyurethanes, polyfluoroelastomers, silicones, polyvinyls, graphite, potassium, centralite, camphor, phthalic ester, nitroguanidine, nitroaminoguanidine, triaminoguanidine nitrate, N-butyl-N(2 nitroxyethyl) nitramine. 
     
     
         10 . The system according to  claim 6 , wherein the barrel includes a portion of conical cross-section followed by a portion of rifled cross-section, the projectile being guided by the sabot in the conical section of the barrel and by direct contact between the projectile and the barrel in the straight section of the barrel.