Aluminum shotgun shell case, methods of making, and using the same

Abstract

The instant disclosure is directed towards shot shell configurations and methods of making the same.

What is claimed is: 
     
         1 . A shell case, comprising:
 a base assembly configured with an upper portion and a lower portion, wherein the lower portion is configured to hold a primer cup; wherein the upper portion is configured to retain a charge, and a sidewall configured to perimetrically extend between the lower portion and upper portion; wherein the sidewall is constructed with a mating edge which extends generally outward from the sidewall adjacent to the lower end; and   a case, the case comprising a mouth end, an open end generally opposed from the mouth end, and a sidewall configured to perimetrically surround the mouth end and extend from the mouth end and extend towards the open end to define an opening therein,   wherein the case is configured with a perimetrical rim adjacent to and configured to extend around the opening;   wherein the mating edge of the base assembly is configured to cooperate with the perimetrical rim of the case to create a rim having a perimetrical seal adjacent to a head end of the shell case.   
     
     
         2 . The shot shell case of  claim 1 , wherein the upper portion and lower portion of the base assembly are integrally formed as a unitary piece. 
     
     
         3 . The shot shell case of  claim 2 , wherein the upper portion and lower portion of the base assembly are attached via mechanical attachment including: a forming operation, crimping, welding, or adhering with a sealant. 
     
     
         4 . The shot shell case of  claim 1 , wherein at least one of the base assembly and the case are constructed from a sheet of an aluminum alloy. 
     
     
         5 . The shot shell case of  claim 1 , wherein at least a portion of the shot shell comprises a surface feature on the aluminum material, 
     
     
         6 . The shot shell case of  claim 5 , wherein the surface feature is configured to provide a coefficient of friction not greater than 0.25. 
     
     
         7 . The shot shell case of  claim 5 , wherein the surface feature provides a reduction to the coefficient of friction between the aluminum shot shell and the barrel of the firearm to an amount of less than 0.45. 
     
     
         8 . The shot shell case of  claim 5 , wherein the surface feature comprises at least one of: a paint; an embossed design; an embossed design with a lacquer overcoat a hologram; a printed component; a grooved surface having raised ridges interspaced with valleys; or a coating. 
     
     
         9 . The shot shell of  claim 8 , wherein the surface feature comprises a coating the coating comprising an organic conformal coating material having flouropolymer therein. 
     
     
         10 . The shot shell of  claim 8 , wherein the surface feature comprises a coating, the coating comprises an anodic coating selected from a Type II or Type III hard anodized coating. 
     
     
         11 . The shot shell of  claim 8 , wherein the surface feature comprises a coating, the coating comprises a ceramic additive. 
     
     
         12 . The shot shell of  claim 11 , wherein the additive is selected from the group consisting of; alumina, titania, zirconia, boron nitride, hexagonal boron nitride, cubic boron nitride, and combinations thereof. 
     
     
         13 . The shot shell of  claim 1 , wherein the base assembly is configured with at least one floatation device. 
     
     
         14 . The shot shell of  claim 1 , wherein the mouth end of the case is configured with a score pattern. 
     
     
         15 . The shot shell of  claim 1 , further comprising a drawn and ironed component; an impact extruded component; a spun formed component; a machined component; and combinations thereof. 
     
     
         16 . The shot shell of  claim 1 , wherein the base assembly is: drawn and ironed; impact extruded; stamp formed; spun formed; machined; or combinations thereof. 
     
     
         17 . The shot shell of  claim 14 , wherein the score pattern is selected from the group consisting of: a radial score pattern; a scroll score pattern; a circumferential score pattern; a cross-hatched score pattern; an x-configuration score pattern, and a circumferential and radial score pattern. 
     
     
         18 . The shot shell of  claim 14 , wherein the score pattern comprises a score residual of at least 0.001″ to not greater than 0.015″, based upon sheet thickness. 
     
     
         19 . The shot shell of  claim 14 , wherein the case is configured with a score mouth around the mouth end of the case. 
     
     
         20 . The shot shell of  claim 14 , wherein the score pattern is configured to eject the entire mouth with retention device upon a firing event, 
     
     
         21 . A shot shell case, comprising:
 a case, the case comprising a head end an open end generally opposed from the head end and a sidewall configured to perimetrically surround the head end and extend from the head end towards the open end to define an opening therein,
 wherein the case is configured with a perimetrical rim having a collar adjacent to and configured to extend around the opening; 
 wherein the head end is configured to with a circumferential rim adjacent to the sidewall, wherein the head end is configured to retain the charge and the primer; and 
   a cap configured to fit onto the open end, wherein the cap is configured with a retention feature designed to secure onto the open end.   
     
     
         22 . The shot shell of  claim 21 , wherein the cap is drawn and ironed; impact extruded; machined; or stamp formed. 
     
     
         23 . The shot shell of  claim 21 , wherein the cap is configured with a score pattern. 
     
     
         24 . The shot shell of  claim 21 , wherein the cap is configured with a retention feature to secure the cap onto the mouth end of the case and hold the cap in place. 
     
     
         25 . The shot shell of  claim 21 , wherein the cap is configured to mechanically attach to the mouth end of the case. 
     
     
         26 . The shot shell of  claim 21 , wherein the cap is configured to snap onto the mouth end of the case. 
     
     
         27 . The shot shell of  claim 21 , wherein the cap is configured to crimp onto the end of the case. 
     
     
         28 . The shot shell of  claim 21 , wherein the cap is configured to attach to the end of the case via: a screw; a weld; glue; a forming operation including a crimp or seam; sealant; and combinations thereof. 
     
     
         29 . The shot shell of  claim 21 , wherein the cap is removably attached to the mouth end via a threaded engagement. 
     
     
         30 . A method comprising:
 drawing an aluminum alloy sheet into a cup;   ironing the sidewall of the cup to bring the case to the desired height;   piercing a center of a mouth end portion of the cup;   bending the metal up to form a recessed portion configured to retain the primer cup; and   removing a center portion when the forming is complete to provide a case configured to fit onto a shot shell.   
     
     
         31 . The method of  claim 30 , further comprising: trimming the formed component. 
     
     
         32 . The method of  claim 30 , further comprising: forming the rim and/or mating edge at the bottom of the at least one: case, base assembly, or cap. 
     
     
         33 . The method of  claim 30 , further comprising: performing a partial redraw to further refine the cup shape. 
     
     
         34 . The method of  claim 30 , further comprising: cleaning the shot shell to remove dirt and lubricant; and applying a surface feature to the case. 
     
     
         35 . The method of  claim 30 , further comprising: spinning the cap over the case to assemble the shot shell. 
     
     
         36 . The method of  claim 30 , further comprising: assembling a plurality of drawn and ironed shot shell components, including:
 a cylindrical case having a mouth end portion a perimetrical sidewall extending up from the mouth end portion with an open end opposed from the mouth end portion;   a base assembly comprising an upper portion configured with a recessed portion; and   a lower portion configured to house a primer.