POLYMER CENTER FIRE CARTRIDGE CASE FOR SMALL OR MEDIUM CALIBER AMMUNITION AND METHOD FOR MANUFACTURING SAME

• US 20160069653A1
• Filed: 09/08/2015
• Published: 03/10/2016
• Est. Priority Date: 09/08/2014
• Status: Abandoned Application

• Current Assignee: Velocity Technologies LLC
• Original Assignee: Velocity Technologies LLC
• Inventors: WALSH, George B.
• Application Number:
  US14/848,089
• Publication Number:
  US 20160069653A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F42B 5/067 Mounting or locking missiles in cartridge cases F42B5/18 takes precedence
• 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 5/313 all elements made of plastics
• CPC Class Codes: F42B 5/36 modified for housing an integral firing-cap

Abstract

An engineered polymer center fire small or medium ammunition cartridge case and methods for manufacturing the same, wherein the engineered polymer material meets the internal & external ballistic standards set by the Sporting Arms and Ammunition Manufacturers Institute and military specifications for center fire rifle small or medium calibers of ammunition cartridges from 0.223 caliber to 30 mm caliber. The cartridge case may allow a projectile to snap into place in the cartridge case mouth after the case is primed and propellant powder is placed into the cartridge case during the cartridge loading process. The rifle cartridge case may be either a single-piece case suitable for use in pistols or a two-piece case suitable for use in rifles, and may be formed by either injection molding or an injection blow molding process. Injection blow molding allows a single piece design. Also disclosed are inventive engineered polymers for use in cartridges.

Claims

1. A method for manufacturing a center fire small or medium caliber ammunition cartridge case from an engineered polymer material, comprising:

providing a nano-composite material resulting from the polymerization of nano-clays which are members of the smectite class of layered silicate or platy minerals which are uniformly dispersed in the polymer matrix; and

molding the nano-composite material to form a cartridge case.

2. The method of claim 1, wherein the cartridge case is a two piece cartridge case.

3. The method of claim 1, wherein an injection molding process or injection blow molding process is used to form the cartridge case, and the cartridge case is a single piece case.

4. The method of claim 1, wherein the cartridge case meets existing Sporting Arms &

Ammunition Manufacturers Institute (SAAMI) and existing military ammunition design specifications for center fire small or medium caliber ammunition cartridge in all calibers from 0.223 to 30 mm calibers.

5. A single piece small or medium caliber polymer ammunition cartridge case, comprising:

a rim; and

a generally cylindrical sidewall integral with the rim;

wherein the rim is positioned to seal a first end of the sidewall, a second end of the sidewall is open to form a mouth, and the sidewall and rim form a cavity; and

wherein a first surface of the rim in the cavity has a primer well formed therein for accepting primer, the primer well having a depth less than a thickness of the rim such that the primer well does not extend through a second surface of the rim opposite the first surface of the rim, thereby allowing primer to be loaded into the primer well only through the mouth.

6. A two piece small or medium caliber polymer ammunition cartridge comprising:

an insert, the insert including a generally cylindrical sidewall and a rim enclosing one end of the sidewall to form a cavity, an outer surface of the sidewall having an annular groove formed therein spaced apart from the rim; and

a generally cylindrical sleeve, the sleeve having an annular locking tab configured to mate with the annular groove of the insert formed on an interior surface;

wherein the insert and sleeve are formed from an engineered polymer material with a flexibility sufficient to allow the sleeve to be placed over the insert so that the annular locking tab of the sleeve mates with the annular groove of the insert, and, when the locking tab of the sleeve is mated with the annular groove of the insert, at least 50% of a length of the insert overlaps the sleeve and at least 50% of a length of the sleeve overlaps the insert.