Keyed jacketed projectile

Abstract

A keyed projectile for use in conventional or conventionally modified weapons systems is disclosed. The projectile core has one or more recessed portions defined in an outer surface. The core is covered with the projectile jacket that locks into the recessed portions to form the keyed projectile. The recessed portions, or keys, can be circumferential grooves, axial grooves, circular grooves, through-holes or any combination thereof. The keyed projectile has an increased resistance to disintegration caused by rotational separation mid-flight due to extremely high levels of RPMs during flight. A method for forming the keyed jacketed projectile is also disclosed.

What is claimed is: 
     
         1 . A keyed projectile, comprising:
 a core having at least one recessed portion defined in an outer surface of the projectile core, the recessed portion defining a depth into the core; and   a jacket covering the projectile core, wherein the jacket has a thickened portion which completely fills the depth of the recessed portion, the thickened portion configured to lock the jacket to the projectile core.   
     
     
         2 . The keyed projectile of  claim 1 , wherein engagement of the thickened portion to the recessed portion maintains co-rotation of the projectile core with the jacket about a common axis of rotation during flight. 
     
     
         3 . The keyed projectile of  claim 1 , wherein the jacket is made from one or more polymer materials. 
     
     
         4 . The keyed projectile of  claim 1 , the recessed portion defines a pattern which preserves rotational symmetry of the keyed projectile to maintain proper balance. 
     
     
         5 . The keyed projectile of  claim 4 , wherein the recessed portion is configured as at least one circular groove. 
     
     
         6 . The keyed projectile of  claim 4 , wherein the recessed portion is configured as at least one circumferential groove. 
     
     
         7 . The keyed projectile of  claim 6 , further comprising an ogive region formed at a forward end of the keyed projectile, wherein the circumferential groove is formed in the ogive region. 
     
     
         8 . The keyed projectile of  claim 6 , further comprising a boat tail region formed at a base end of the keyed projectile, wherein the circumferential groove is formed proximate to the boat tail region. 
     
     
         9 . The keyed projectile of  claim 1 , comprising two recessed portions, wherein each recessed portion is configured as a circumferential groove. 
     
     
         10 . The keyed projectile of  claim 1 , wherein the recessed portion is configured as at least one axial groove. 
     
     
         11 . The keyed projectile of  claim 1 , comprising a plurality of recessed portions, wherein each of the recessed portions is configured as an axial groove symmetrically spaced apart in the outer surface. 
     
     
         12 . The keyed projectile of  claim 11 , further comprising an ogive region formed at a forward end of the keyed projectile and a boat tail region formed at a base end of the keyed projectile, wherein each of the plurality of axial grooves extends from the ogive region to boat tail region. 
     
     
         13 . The keyed projectile of  claim 1 , comprising a plurality of recessed portions. 
     
     
         14 . The keyed projectile of  claim 13 , wherein at least one of the plurality of recessed portions is a circumferential groove. 
     
     
         15 . The keyed projectile of  claim 13 , wherein at least one of the plurality of recessed portions is an axial groove. 
     
     
         16 . The keyed projectile of  claim 13 , wherein at least one of the plurality of recessed portions is a circular groove. 
     
     
         17 . The keyed projectile of  claim 13 , wherein the plurality of recessed portions is a combination of at least one circumferential groove, at least one axial groove and at least one circular groove. 
     
     
         18 . A method for making a keyed projectile, comprising:
 forming a projectile core;   forming at least one recessed portion in an outer surface of the projectile core;   molding a jacket over the projectile core from one or more polymer materials.   
     
     
         19 . The method of  claim 18 , wherein the step of forming the projectile core further comprises forming an inward taper at a forward end defining an ogive region and forming an inward taper at a base end defining a boat tail region. 
     
     
         20 . The method of  claim 18 , wherein the step of forming at least one recessed portion in the outer surface further comprises machining at least one recessed portion selected from a group consisting of a circumferential groove, an axial groove and a circular groove.