Base insert for polymer ammunition cartridges

• US 9,599,443 B2
• Filed: 09/10/2014
• Issued: 03/21/2017
• Est. Priority Date: 07/30/2010
• Status: Active Grant

• Current Assignee: Pcp Tactical, LLC
• Original Assignee: Pcp Tactical, LLC
• Inventors: Padgett, Charles, Wiley, Sy
• Primary Examiner(s): MORGAN, DERRICK R
• Application Number:
  US14/482,843
• Publication Number:
  US 20140373744A1
• Time in Patent Office: 923 Days
• US Class Current: 1/1
• CPC Class Codes: B29C 65/72 by combined operations or combined techniques, e.g. welding and stitching
• CPC Class Codes: B29C 69/001 a shaping technique combined with cutting, e.g. in parts or slices combined with rearranging and joining the cut parts for reinforced material B29C70/545; B29C49/4278, B29C51/268 take precedence
• CPC Class Codes: B29K 2096/00 Use of specified macromolecular materials not provided for in a single one of main groups B29K2001/00 - B29K2095/00, as moulding material
• CPC Class Codes: B29L 2031/7772 Cartridges
• CPC Class Codes: F42B 3/24 Cartridge closures or seals top closures for shotgun ammunition cartridges F42B7/12
• CPC Class Codes: F42B 33/00 Manufacture of ammunition; Dismantling of ammunition; Apparatus therefor F42B5/188 takes precedence; manufacturing processes for hollow charges F42B1/036; manufacture of blasting cartridge initiators F42B3/195
• 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: F42C 19/083 characterised by the shape and configuration of the base element embedded in the cartridge bottom, e.g. the housing for the squib or percussion cap
• CPC Class Codes: F42C 19/10 Percussion caps

Abstract

An insert for a high strength polymer-based cartridge casing can include an outside, an inside formed within the insert, and a back end disposed at a rear of the cartridge casing. The back end includes a rim and groove disposed around the outside of the insert and a primer pocket disposed inside the back end. Also included is a front end, opposite the back end, having an overmolded area disposed around the outside of the insert above the primer pocket and a basin, having a depth, formed inside the overmolded area. A flash hole can be included inside the insert and communicating between the primer pocket and the basin. The flash hole has a perimeter and a ring disposed around the perimeter of the flash hole, including a height starting at a bottom of the basin, disposed toward the front end, and less than the depth of the basin.

Claims

1. A high strength polymer-based cartridge casing comprising:

a cartridge body, molded from a polymer, comprising;

a first end having a mouth; and

a second end opposite the first end;

an outer sheath disposed proximate the second end;

a lower bowl disposed proximate the outer sheath and having a hole therethrough;

an insert, formed from at least one of a metal and metal alloy, comprising a front end and a back end, and further comprising;

a rim disposed at the back end;

a primer pocket disposed at and open along a portion of the back end and continuing partially toward the front end;

a flash hole disposed forward of the primer pocket, in fluid communication with the primer pocket, and continuing partially toward the front end; and

an overmolded area formed at the front end, opposite the rim, comprising;

a basin formed on an inside of the overmolded area and disposed above the primer pocket; and

a ring formed, at a bottom of the basin, on an inside of the overmolded area, and surrounding the flash hole, comprising a ring wall;

wherein the ring prevents polymer from the lower bowl from flowing into the flash hole by stopping the polymer at the ring wall;

wherein the second end of the cartridge body engages with the front end of the insert;

wherein the outer sheath is disposed to an outside of the overmolded area;

wherein the lower bowl is disposed inside of the overmolded area and in contact with the basin; and

wherein the hole in the lower bowl is disposed around the ring wall.

2. The high strength polymer-based cartridge casing of claim 1, wherein during a powder ignition in a firearm, the lower bowl presses against the basin and the outer sheath contacts the firearm to create a compression effect against the overmolded area.

3. The high strength polymer-based cartridge casing of claim 1, wherein the insert further comprises:

a ridge formed on the overmolded area; and

a key formed on the ridge;

wherein both the ridge and the key engage the outer sheath, and

wherein the key comprises at least one of a flat portion, a raised portion, or dimples.

4. A method of making a high strength polymer-based cartridge casing comprising the steps of:

forming an insert from at least one of a metal and metal alloy, comprising a front end and a back end, and further forming;

a rim disposed at the back end;

a primer pocket disposed at and open along a portion of the back end and continuing partially toward the front end;

a flash hole disposed forward of the primer pocket, in fluid communication with the primer pocket, and continuing partially toward the front end; and

an overmolded area formed at the front end, opposite the rim, comprising;

a basin formed on an inside of the overmolded area and disposed above the primer pocket; and

a ring formed, at a bottom of the basin, on an inside of the overmolded area, and surrounding the flash hole, comprising a ring wall;

molding a cartridge body using a polymer comprising the steps of;

molding the polymer to form an outer sheath disposed proximate the second end and to an outside of the overmolded area;

molding a lower bowl disposed proximate the outer sheath, inside of the overmolded area, in contact with the basin, and having a hole therethrough; and

stopping the polymer at the ring wall.

5. The method of making a high strength polymer-based cartridge casing of claim 4, wherein forming the insert further comprises the steps of:

forming a ridge on the overmolded area; and

forming a key on the ridge with at least one of a flat portion, a raised portion, or dimples;

wherein both the ridge and the key engage the outer sheath.