Patent ID: 6575098
Filing Date: 2003-06-10
Classification: F42B

Abstract:
A practice cartridge for use in a firearm, the firearm having a chamber defining a shoulder and a recoil mechanism, the cartridge comprising:a cartridge case having a bottom portion and a front-end portion with an inner diameter and an inclined groove formed on the inner wall of the cartridge case; a primer disposed in the bottom portion of the cartridge case; a sabot having a front-end portion with a larger diameter and a rear-end portion with a smaller diameter, the rear-end portion having a substantially closed bottom, wherein the outer diameter of the rear-end portion is substantially the same as the inner diameter of the inner wall of the cartridge case to allow the rear-end portion to fit hermetically into the case and form a substantially hermetic space with the bottom of the cartridge case, a groove is formed on the outer surface of the rear-end portion of the sabot, the front-end portion of the sabot is adapted to be propelled against the shoulder of the chamber, and the rear-end portion of the sabot has an orifice communicating the hermetic space with the front-end portion allowing a propellant gas trapped within the hermetic space to bleed through to the front-end portion; and an elastic limiting element disposed in the groove of the sabot, wherein, upon percussion, the cartridge case slides relative to the sabot moving the inclined groove of the cartridge case towards the limiting element, when the inclined groove arrives at the limiting element, the limiting element expands outwardly due to the elasticity engaging with the inclined groove of the cartridge case, thereby limiting the movement of the cartridge case relative to the sabot.