Shear fragmenting bullet

Abstract

A bullet has a jacket and a core seated into the jacket. The core consists of helically formed strands of malleable material swaged into a cylindrical shape. The strands have a uniform pitch along the core, and fragment uniformly into small portions upon impact. A method of making a bullet includes providing helically formed strands of malleable material, swaging the strands, and seating the strands into a jacket.

What is claimed is:  
     
         1 . A bullet comprising: 
 a metal jacket, of substantially uniform wall thickness, having an enclosed base and a substantially cylindrical body extending transverse said base, and    a core having a plurality strands of a malleable material having a low shear modulus, said strands being helically formed together in a spiral configuration and swaged into a uniform solid cylinder having a selected precise mass, with each said strand extending rotationally and obliquely in a continuous fashion around said cylinder, said core being seated within said jacket against said base.    
     
     
         2 . The bullet as set forth in  claim 1  wherein said body of said jacket has an inwardly tapering tip opposite said base, said tip being created by point forming.  
     
     
         3 . The bullet as set forth in  claim 1  wherein said material of said strands has a shear modulus less than 3.5 million pounds per square inch.  
     
     
         4 . The bullet as set forth in  claim 1  wherein said material of said strands is chosen from the group of lead, lead alloy, tin, magnesium and aluminum.  
     
     
         5 . The bullet as set forth in  claim 1  wherein said plurality of strands includes from two to fifteen strands.  
     
     
         6 . The bullet as set forth in  claim 1  wherein each said strand has a pitch of between one half and five turns per inch around said cylinder.  
     
     
         7 . A bullet comprising: 
 a metal jacket, of substantially uniform wall thickness, having an enclosed base and a substantially cylindrical body extending transverse said base, said jacket having an inwardly tapering tip opposite said base, said tip being created by point forming, and    a core having from two to fifteen strands of a malleable material, said material of said strands having a shear modulus of less than 3.5 million pounds per square inch and being chosen from the group of lead, lead alloy, tin, magnesium and aluminum, said strands being helically formed together in a spiral configuration and swaged into a uniform solid cylinder having a selected precise mass, with each said strand extending rotationally and obliquely in a continuous fashion around said cylinder at a pitch of between one half and five turns per inch, said core being seated within said jacket against said base.    
     
     
         8 . A method of making a bullet comprising the steps of: 
 providing a plurality of strands of helically formed together in a spiral configuration, said strands being of malleable material having a low shear modulus,    swaging said strands into a uniform solid cylindrical core having a selected precise mass, with each said strand extending rotationally and obliquely in a continuous fashion about said core,    providing a jacket, of substantially uniform wall thickness, having an enclosed base and a substantially cylindrical body extending transverse said base, and    seating said core into said jacket.    
     
     
         9 . The method as set forth in  claim 8  further comprising the step of point forming said jacket after said step of seating said core, said point forming creating an inwardly tapering tip on said body of said jacket, opposite said base.  
     
     
         10 . The method as set forth in  claim 8  wherein said material of said strands has a shear modulus less than 3.5 million pounds per square inch.  
     
     
         11 . The method as set forth in  claim 8  wherein said material of said strands is chosen from the group of lead, lead alloy, tin, magnesium and aluminum.  
     
     
         12 . The method as set forth in  claim 8  wherein said plurality of strands includes from two to fifteen strands.  
     
     
         13 . The method as set forth in  claim 8  wherein each said strand has a pitch of between one half and five turns per inch around said core.  
     
     
         14 . A method of making a bullet comprising the steps of: 
 providing from two to fifteen strands of helically formed together in a spiral configuration, said strands being of malleable material, said material of said strands having a shear modulus of less than 3.5 million pounds per square inch and being chosen from the group of lead, lead alloy, tin, magnesium and aluminum,    swaging said strands into a uniform solid cylindrical core having a selected precise mass, with each said strand extending rotationally and obliquely in a continuous fashion about said core at a pitch of between one half and five turns per inch,    providing a jacket, of substantially uniform wall thickness, having an enclosed base and a substantially cylindrical body extending transverse said base    seating said core into said jacket, and    point forming said jacket after said step of seating said core, said point forming creating an inwardly tapering tip on said body of said jacket, opposite said base