Ammunition sealant flow features

Abstract

A polymer ammunition cartridge that includes a cartridge body extending from the base end and a cartridge nose extending from the body is disclosed. The cartridge nose has a shoulder and a neck that extends to a projectile opening forming a distal end of the cartridge. Defined on the inner surface of the neck at an intermediate position between the shoulder and the projectile opening is an annular shelf. The neck further includes at least one wicking groove formed on the inner surface and extending from the projectile opening to the annular shelf. The wicking groove is configured to receive adhesive after a bullet has been installed into the neck and the annular shelf arrests the flow of adhesive thereby structurally limiting bondage between the neck and a bullet to the longitudinal length of the wicking grooves.

What is claimed is: 
     
         1 . A polymer ammunition cartridge having a base end and a cartridge body extending from the base end and a cartridge nose extending from the cartridge body, the cartridge nose comprising:
 a shoulder and a neck, the neck extending to a projectile opening at a distal end of the cartridge;   an annular shelf defined at an intermediate location between the projectile opening and the shoulder; and   at least one wicking groove defined on an inner surface of the neck and extending from the projectile opening to the annular shelf.   
     
     
         2 . The cartridge of  claim 1 , further comprising a plurality of wicking grooves defined on the inner surface of the neck. 
     
     
         3 . The cartridge of  claim 2 , wherein the plurality of wicking grooves are substantially radially symmetrically disposed about the inner diameter of the neck. 
     
     
         4 . The cartridge of  claim 2 , wherein at least one of the plurality of wicking grooves defines a longitudinal axis that is parallel to a longitudinal axis of the cartridge. 
     
     
         5 . The cartridge of  claim 2 , wherein each wicking groove has a length substantially equal to each other wicking groove. 
     
     
         6 . The cartridge of  claim 2 , further comprising an annular groove defined about the inner surface of the neck. 
     
     
         7 . The cartridge of  claim 6 , wherein the annular groove is formed between the projectile opening and the annular shelf. 
     
     
         8 . The cartridge of  claim 7 , wherein the at least one wicking groove connects to the annular groove. 
     
     
         9 . The cartridge of  claim 7 , wherein the annular groove integrally connects with each of the wicking grooves. 
     
     
         10 . The cartridge of  claim 2 , wherein at least two of the wicking grooves have different maximum lengths. 
     
     
         11 . The cartridge of  claim 1 , wherein the at least one wicking groove is configured to receive an adhesive after a bullet has been installed in the cartridge. 
     
     
         12 . The cartridge of  claim 11 , wherein the at least one wicking groove and the adhesive are configured to generate a bullet pull value of at least 60 pounds of force. 
     
     
         13 . The cartridge of  claim 1 , wherein the neck between the shoulder and the annular shelf has a uniform inner diameter. 
     
     
         14 . The cartridge of  claim 1 , wherein the neck between annular shelf and the shoulder is configured to cause diametric interference with a bullet installed in the cartridge. 
     
     
         15 . The cartridge of  claim 1 , wherein the annular shelf is configured to arrest flow of an adhesive introduced through the at least one wicking groove. 
     
     
         16 . The cartridge of  claim 1 , wherein the at least one wicking groove comprises a spiral groove. 
     
     
         17 . A nose for a polymer ammunition cartridge, the nose comprising:
 a shoulder having a shoulder coupling joint and a neck opposite the shoulder coupling joint, the neck defining a length terminating in a projectile opening;   an annular shelf formed along the length of the neck between the projectile opening and the shoulder; and   a plurality of wicking grooves defined on an inner surface of the neck and terminating at the annular shelf, the wicking grooves configured as an adhesive flow path from the projectile opening to the annular shelf.   
     
     
         18 . The nose of  claim 17 , wherein the plurality of wicking grooves extend from the projectile opening to the annular shelf. 
     
     
         19 . The nose of  claim 18 , wherein the plurality of wicking grooves are parallel to a longitudinal axis of the nose. 
     
     
         20 . The nose of  claim 17 , further comprising a uniform inner neck diameter defined between the annular shelf and the shoulder that is less than an inner neck diameter defined between the projectile opening and the annular shelf.