CARTRIDGE CASES AND BASE INSERTS THEREFOR

• US 20120060716A1
• Filed: 09/02/2011
• Published: 03/15/2012
• Est. Priority Date: 09/10/2010
• Status: Active Grant

• Current Assignee: Nylon Corporation of America, Inc.
• Original Assignee: Nylon Corporation of America, Inc.
• Inventors: Davies, Jack D., Biederman, Greg, Coco, Christopher A.
• Granted Patent: US 8,522,684 B2
• Time in Patent Office: Days
• US Class Current: 102/469
• CPC Class Codes: F42B 5/26 Cartridge cases F42B5/18 takes precedence ; manufacturing of cartridge cases B21K21/04
• CPC Class Codes: F42B 5/307 formed by assembling several elements

Abstract

A base insert for a cartridge case comprises a base end having a lip and a groove proximate the lip and having a primer pocket defined in the base end and an insert end having a base wall and a cylindrical wall extending there from, the base wall and cylindrical wall defining a powder fill pocket. The base wall has a flash hole disposed therein and an inner surface facing the powder fill pocket. The cylindrical wall has an inner surface intersecting with the inner surface of the base wall and an outer surface defining the outer circumference of the base insert. The intersection of the inner surface of the base wall and the inner surface of the cylindrical wall is curved or forms an oblique angle, while the outer surface of the insert end is not curved and does not form an oblique angle.

Claims

1. A base insert for a cartridge case comprising:

a base end having a lip and a groove proximate the lip and having a primer pocket defined in the base end;

an insert end having a base wall and a cylindrical wall extending there from, said base wall and cylindrical wall defining a powder fill pocket;

wherein said base wall has a flash hole disposed therein and an inner surface facing the powder fill pocket;

wherein said cylindrical wall has an inner surface intersecting with the inner surface of the base wall and an outer surface defining the outer circumference of the base insert;

wherein the intersection of said inner surface of the base wall and the inner surface of the cylindrical wall is curved, while the outer surface of the insert end is not curved.

2. The base insert as claimed in claim 1, wherein the inner surface of the base wall is substantially orthogonal to the outer surface of the cylindrical wall, while the inner surface of the cylindrical wall is substantially parallel to the cylindrical wall.

3. The base insert as claimed in claim 1, wherein the inner surface of the base wall is substantially orthogonal to the outer surface of the cylindrical wall, while the inner surface of the cylindrical wall is substantially slanted and not parellel to the cylindrical wall.

4. The base insert as claimed in claim 3, wherein the cylindrical wall has a tapering thickness, wherein the cylindrical wall is thicker proximate its intersection with the base wall and thinner distal from the base wall.

5. The base insert as claimed in claim 3, wherein the inner surface of the base wall include a curved cut-out contiguous with the curvature of the intersection of the inner surface of the base wall and the inner surface of the cylindrical wall.

6. The base insert as claimed in claim 3, wherein the inner surface of base wall includes a curved cut-out adjacent to and surrounding the flash hole.

7. The base insert as claimed in claim 5, wherein the inner surface of base wall includes a curved cut-out adjacent to and surrounding the flash hole.

8. The base insert as claimed in claim 3, wherein the base wall includes an annular flashhole cutoff pit disposed therein.

9. A base insert for a cartridge case comprising:

a base end having a lip and a groove proximate the lip and having a primer pocket defined in the base end;

an insert end having a base wall and a cylindrical wall extending there from, said base wall and cylindrical wall defining a powder fill pocket;

wherein said base wall has a flash hole disposed therein and an inner surface facing the powder fill pocket;

wherein said cylindrical wall has an inner surface intersecting with the inner surface of the base wall and an outer surface defining the outer circumference of the base insert;

wherein the intersection of said inner surface of the base wall and the inner surface of the cylindrical wall forms an oblique angle, while the intersection of the base wall with the outer surface of the of the cylindrical wall does not form an oblique angle.

10. A base insert for a cartridge case made from the base insert with a polymer over molded with the base insert, the base insert comprising:

a cylindrical wall

a first radially indented polymer groove adjacent the cylindrical wall,

and a second radially indented polymer groove in the cylindrical wall,

wherein an extraction groove is formed in the cartridge case near the first radially indented polymer groove when the polymer is molded over the base insert.