Firearms

Abstract

A barrel assembly comprising a barrel ( 37 ); a plurality of projectiles ( 30 ) axially disposed within the barrel for operative sealing engagement with a bore ( 36 ) of the barrel; and a plurality of discrete propellant charges for propelling each projectile of the plurality of projectiles sequentially through a muzzle of the barrel ( 37 ). Each projectile of the plurality of projectiles includes a tapered anvil portion ( 31 ); a sealing portion ( 35 ) extending about the tapered anvil portion for sealing engagement with the bore ( 36 ) of the barrel ( 37 ) upon the projectile being inserted into the barrel before firing, the sealing portion being forwardly moveable relative to the tapered anvil portion for operative freeing from the tapered anvil portion and for providing a bypass passage between propellant charges. The tapered anvil portion ( 31 ) includes an anvil extension forming a spine ( 33 ) abutting the tapered anvil portion of a trailing projectile of the plurality of projectiles, whereby if the tapered anvil portion of the trailing projectile of the plurality of projectiles has an increased resistance to forward movement, the sealing portion ( 35 ) of the trailing projectile is urged to move forward along the tapered anvil portion by exposure of a rear face ( 38 ) of the sealing portion to respective ones of the plurality of discrete propellant charges for forward propulsion of the sealing portion ( 35 ) relative to the tapered anvil portion ( 31 ).

1 . A method of minimising misfiring or alleviating their consequences in a barrel of the type described including: 
 forming at least each trailing projectile with a sealing portion extending about a tapered anvil portion and moveable therealong for expansion into sealing engagement with the barrel bore, and    providing disengagement means for operatively disengaging the sealing portion from the anvil portion in response to ignition of the propellant charge associated with the projectile.    
     
     
         2 . The method as claimed in  claim 1  for minimising the effect of a hang fire, wherein the disengagement means is constituted by an anvil extension in the form of a spine placing the anvil portion of a trailing projectile in columnar relationship with the anvil portion of the adjacent leading projectile to increase the resistance to forward movement of the trailing anvil portion and enabling the sealing portion to move forward along the anvil portion for operative disengagement therefrom.  
     
     
         3 . The method as claimed in  claim 2 , wherein the anvil extension includes a central front extension column extending to the front of the sealing portion and a central rear extension column extending beyond the sealing portion and defining a propellant space between the adjacent abutting projectiles.  
     
     
         4 . The method as claimed in  claim 1  for minimising the effect of a hang fire, wherein the disengagement means is constituted by a pressure sensitive leverage system connected between the anvil portion and the sealing portion which operates when pressures in the barrel behind the projectile increases beyond a safe operating pressure to lever the sealing portion along the anvil portion to a disengaged position.  
     
     
         5 . The method as claimed in  claim 1  for enabling effective discharge of projectiles loaded with high barrel engaging forces, wherein the disengagement means is constituted by a hammer member supported for free forward movement into a cavity formed in the exposed rear end of the anvil portion such that the hammer member is driven forward upon ignition of the associated propellant charge to impart its energy to the anvil portion by impact so as to jolt the anvil portion from operative sealing engagement with the sealing portion.  
     
     
         6 . The method as claimed in  claim 5 , wherein each projectile include a tapered sealing portion in the form of a malleable band extending about a complementary tapered anvil portion such that forward movement of the anvil portion relative to the sealing portion operatively disengages the anvil portion therefrom.  
     
     
         7 . The method as claimed in  claim 5 , wherein the cavity in which the hammer member is supported is a blind cavity formed such that in operation upon ignition of the propellant charge, the hammer strikes the end wall of the blind cavity.  
     
     
         8 . A barrel of the type described, wherein: 
 each trailing projectile has a sealing portion extending about a tapered anvil portion and arranged in sealing engagement with the barrel bore and moveable forwardly therealong for operative freeing from the anvil portion;    a spine extends from each anvil portion placing the anvil portions in columnar relationship with the barrel, and    the rear part of each sealing projectile is exposed to their respective propellant charges for forward propulsion relative to the anvil portion about which they extend when forward movement of such anvil portions is resisted.    
     
     
         9 . A barrel of the type described, wherein: 
 each projectile includes a sealing portion extending about a tapered anvil portion and loaded into the barrel with high barrel engaging forces by relative forward movement of the sealing portion along the anvil portion;    each projectile includes a hammer member supported for free forward movement into a cavity formed in the exposed rear end of the anvil portion, and    each hammer member being exposed, in use, to its ignited propellant for forward acceleration to impart its energy to the anvil portion by impact so as to jolt the anvil portion from operative sealing engagement with the sealing portion.    
     
     
         10 . A barrel as claimed in  claim 9 , wherein each projectile includes a tapered sealing portion in the form of a malleable band extending about a complementary tapered anvil portion, and the cavity in which the hammer member is supported is a blind cavity such that in operation upon ignition of the propellant charge, the hammer strikes the end wall of the blind cavity.  
     
     
         11 . A barrel of the type described, wherein: 
 each projectile includes a sealing portion extending about a tapered anvil portion and loaded into the barrel by relative forward movement of the sealing portion along the anvil portion;    each projectile includes a pressure sensitive leverage system connected between the anvil portion and the sealing portion which operates when pressures in the barrel behind the projectile increases beyond a safe operating pressure to lever the sealing portion rearwardly along the anvil portion to a disengaged position.    
     
     
         12 . A barrel assembly substantially as hereinbefore described with reference to either of the accompanying drawings.