Patent ID: 9739579
Date: 2017-08-22
CPC Classifications: F42B,F42C

Claim:
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.