Granted Patent B2

US 9,739,579 · App. 14/822,183 · Granted Aug 22, 2017

Abstract

Claims (25)

1. A firearm ammunition cartridge comprising:

a case having a substantially tubular body portion, an open leading end, and a trailing end defining a primer port, said primer port opening to an interior of said case;

an insert received within said case and extending along said body portion, said insert having an exterior surface conforming to an interior surface of said body portion and a central cavity extending along an axial dimension of said insert, said central cavity opening to said primer port at said trailing end of said case and opening to a leading end of said insert;

a quantity of gunpowder disposed within said central cavity; and

a projectile received and retained within said leading end of said case;

whereby said gunpowder is confined to a chamber comprising at least a portion of said central cavity between said case trailing end and said projectile;

wherein said central cavity is configured to define at least a cylindrical first portion having a first diameter, and a cylindrical second portion having a second diameter, the second diameter being formed sufficiently larger than the first diameter such that a majority of said gunpowder is maintained within said second portion;

said central cavity defining the first portion as a leading portion having the first diameter and the second portion as a trailing portion having the second diameter; and

whereby the insert is configured to remain in the case after combustion of the gunpowder.

2. The firearm ammunition cartridge of claim 1 , wherein a trailing end of said projectile closes a leading end of said central cavity.

3. The firearm ammunition cartridge of claim 2 wherein said quantity of gunpowder defines a volume approximately equal to a volume of said central cavity between said trailing end of said projectile and said trailing end of said case.

4. The firearm ammunition cartridge of claim 1 , said first portion and said second portion of said central cavity being coaxial with one another and with an axial dimension of said primer port.

5. The firearm ammunition cartridge of claim 4 , said first portion being configured as a leading portion of said central cavity having a diameter substantially equal to a trailing end of said projectile.

6. The firearm ammunition cartridge of claim 5 , said trailing end of said projectile being received within said leading portion of said central cavity.

7. The firearm ammunition cartridge of claim 4 , said central cavity further defining a cylindrical third portion having a third diameter.

8. The firearm ammunition cartridge of claim 7 , said first portion defined as a leading portion of said central cavity having a diameter substantially equal to a trailing end of said projectile, said third portion defined as a trailing portion of said central cavity having a diameter substantially equal to a diameter of said primer port, and said second portion defined as a central portion of said central cavity having a diameter greater than said diameter of said leading portion and said diameter of said trailing portion, said trailing end of said projectile being received within said leading portion of said central cavity.

9. The firearm ammunition cartridge of claim 4 , said insert being fixed within said case.

10. The firearm ammunition cartridge of claim 9 , said case defining a tapered portion between said body portion and said leading end, said exterior surface of said insert having a leading portion conforming to an interior surface of said tapered portion of said case, whereby said tapered portion retains said insert within said case between said tapered portion and said trailing end of said case.

11. The firearm ammunition cartridge of claim 1 , wherein the insert is configured to be non-combustible.

12. The firearm ammunition cartridge of claim 1 , wherein the insert is formed of a rigid material configured to withstand the combustion of the gunpowder without deformation.

13. An insert for a firearm ammunition case comprising:

a substantially rigid member defining a leading end, an opposite trailing end, and an exterior surface between said leading and trailing ends, said exterior surface being shaped to conform to at least a portion of an interior surface of a firearm ammunition case between a trailing end of the case and a leading tapered portion of the case, said member further defining a central cavity extending between and opening to said leading and trailing ends of said member, said central cavity being sized to receive a quantity of gunpowder therein, said central cavity being configured to define at least a cylindrical first portion having a first diameter, and a cylindrical second portion having a second diameter, the second diameter being formed sufficiently larger than the first diameter such that a majority of said gunpowder is maintained within said second portion, said central cavity defining the first portion as a leading portion having the first diameter and the second portion as a trailing portion having the second diameter, and said substantially rigid member being configured to remain in the case after combustion of the gunpowder.

14. The insert of claim 13 , said exterior surface defining a tapered portion proximate said leading end, said tapered portion being shaped to conform to an interior surface of a tapered portion of a firearm ammunition case.

15. The insert of claim 13 , said leading portion of said central cavity having a diameter substantially equal to a trailing end of an ammunition projectile.

16. The insert of claim 13 , said first portion and said second portion of said central cavity being coaxial with one another and with an axial dimension of said exterior surface.

Assignments (7)