Polymeric ammunition casing geometry

• US 9,335,137 B2
• Filed: 10/06/2015
• Issued: 05/10/2016
• Est. Priority Date: 07/28/2011
• Status: Active Grant

• Current Assignee: Make-Up Art Cosmetics Incorporated (The Estee Lauder Companies Inc.)
• Original Assignee: Make-Up Art Cosmetics Incorporated (The Estee Lauder Companies Inc.)
• Inventors: Maljkovic, Nikica, Bosarge, John Francis Jr., Gibbons, Joe Paul Jr.
• Primary Examiner(s): Bergin, James S
• Application Number:
  US14/876,497
• Publication Number:
  US 20160040970A1
• Time in Patent Office: 217 Days
• Field of Search: 102/464, 102/465, 102/466, 102/467, 102/469, 102/470, 102/447, 86/18
• US Class Current: 1/1
• CPC Class Codes: F42B 33/001 Devices or processes for assembling ammunition, cartridges or cartridge elements from parts
• CPC Class Codes: F42B 33/10 Reconditioning used cartridge cases F42B33/004 takes precedence
• CPC Class Codes: F42B 5/02 Cartridges, i.e. cases with charge and missile
• CPC Class Codes: F42B 5/025 characterised by the dimension of the case or the missile
• CPC Class Codes: F42B 5/26 Cartridge cases F42B5/18 takes precedence ; manufacturing of cartridge cases B21K21/04
• CPC Class Codes: F42B 5/30 of plastics , i.e. the cartridge-case tube is of plastics
• CPC Class Codes: F42B 5/307 formed by assembling several elements
• CPC Class Codes: F42B 5/34 with provision for varying the length

Abstract

An ammunition cartridge casing having a geometry designed to allow for the use of polymeric materials in forming the walls of the cartridge casing of an ammunition article, and methods of reusing such cartridges are provided. More specifically, the ammunition cartridge has a specified ratio between the wall-thicknesses of select portions of an ammunition article'"'"'s cartridge casing such that polymeric materials may be used in the construction of the ammunition article cartridge casings.

Claims

1. A method of reusing an ammunition article comprising:

providing a casing defining a generally cylindrical hollow body having a metallic cap at a first end thereof and a caselet at a second end thereof, the caselet having a proximal end defining a body region and a distal end defining a neck region, wherein the cap is interconnected with the proximal end of said caselet such that the casing at least partially encloses an internal volume, and wherein the diameter of the caselet narrows from a first diameter at the body region to a second diameter at the neck region, the casing having a propellant disposed and confined within said internal volume and a primer disposed at the first end of said casing in combustible communication with said propellant, wherein the caselet at least partially comprises a substantially polymeric material, and wherein the ratio of the minimum thickness of the wall of the body region of the said caselet to the mid-point of the tolerance range of the wall thickness of the neck region of the ammunition casing is greater than 1.5;

firing the ammunition article; and

discarding the fired polymeric caselet, retaining the fired metallic cap and attaching a new polymeric caselet to the existing metallic cap.

2. The method according to claim 1, wherein the cap and casing are threadingly interconnected.

3. The method according to claim 2, wherein the headspace of the ammunition article is adjusted by rotating the threads clockwise and/or counterclockwise until a desired headspace distance is reached.

4. The method according to claim 1, wherein the ratio of the minimum thickness of the wall of the body region of the said caselet to the mid-point of the tolerance range of the wall thickness of the neck region of the ammunition casing is greater than 2.

5. The method according to claim 1, wherein the casing is one-piece.

6. The method according to claim 1, wherein the polymeric material comprises one of either polyphenylsulfone or polycarbonate.

7. The method according to claim 1, wherein polymeric material comprises a polymeric material possessing a glass transition temperature of less than 250°

C.

8. The method according to claim 1 wherein said polymeric material additionally comprises at least one additive selected from the group consisting of plasticizers, lubricants, molding agents, fillers, thermo-oxidative stabilizers, flame-retardants, coloring agents, compatibilizers, impact modifiers, release agents, reinforcing fibers.

9. The method according to claim 1, wherein the cap comprises a material selected from the group consisting of steel, aluminum alloy, brass, a magnesium alloy, and a polymer.

10. The method according to claim 1, wherein the cap and the caselet are joined using an interconnection selected from the group consisting of a snap fit, threads, snap fit in conjunction with an adhesive, and threads in conjunction with an adhesive.

11. The method according to claim 1, wherein the caselet is closed at its distal end and contains no projectile.

12. The method according to claim 1 additionally comprising a projectile fitted into the distal end of the caselet.

13. The method according to claim 12 wherein the projectile is secured to the casing by an interconnection selected from the group consisting of molding the polymeric material around the projectile, mechanical interference, an adhesive, ultrasonic welding, the combination of molding in place and adhesive, and hot crimping after molding.

14. The method according to claim 1, wherein the ratio of the minimum thickness of the wall of the body region of the said caselet to the average wall thickness of the neck region of the ammunition casing, as defined by the middle of its tolerance range, is greater than 5 and has less than 70% of the internal volume of a corresponding standard brass case of identical caliber.

15. The method according to claim 1, additionally comprising a projectile fitted in the second end and wherein the said projectile'"'"'s velocity when fired does not exceed 1,086 feet per second at standard atmospheric conditions.

16. The method according to claim 15, wherein the projectile is secured to the casing by an interconnection selected from the group consisting of molding the polymeric material around the projectile, mechanical interference, an adhesive, ultrasonic welding, the combination of molding in place and adhesive, and hot crimping after molding.

17. The method according to claim 1, wherein the polymeric material comprises one of either a transparent or translucent polymeric material.