Modular case ammunition and methods of assembly

Abstract

A hybrid ammunition cartridge for a firearm is includes a substantially cylindrical casing defining a body portion having a neck at a forward end and a base at a rearward end, the base including a rim. A projectile is mounted in the neck. Brass is used in the casing at the neck to hold the projectile at the proper crimp. Brass is also used in the rim to house the primer and to provide a surface at which a hook or any suitable mechanism can be used to extract the cartridge from the firearm. The remaining body portion is then manufactured from a composite material having suitable mechanical properties.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of U.S. Provisional Patent Application No. 61 / 175,906, filed on May 6, 2009, the content of which is incorporated herein by reference in its entirety.TECHNICAL FIELD[0002]The present invention relates to ammunition and, more particularly, to ammunition that can be assembled in a modular fashion from separate components and methods for assembling such ammunition.BACKGROUND OF THE INVENTION[0003]Standard ammunition cartridges for firearms are typically unitary in construction with the structural components of the cartridge being made from metal. In general, the cartridge includes four sections, namely, a casing of a generally cylindrical shape and terminated at a rearward end by a rim, a propellant contained in the casing, a primer located at the rearward end, and a bullet or projectile frictionally held in a forward end of the casing. The casing is sized to a particular caliber, which closely approximates...

AI Technical Summary

Benefits of technology

[0008]In one aspect, a hybrid ammunition cartridge for use in a firearm is disclosed herein. This hybrid ammunition cartridge includes a substantially cylindrical skeleton casing defining a body portion having a neck at a forward end and a base at a rearward end, the base including a rim. A projectile is mounted in the neck of the skeleton casing. A suitable material such as (but not limited to) brass is used in the skeleton casing at the neck to frictionally retain the projectile at the proper crimp. This suitable material can also be used in the rim to house the primer and to provide a surface at which a suitable mechanism can be used to extract the cartridge from the firearm. As will be explained in greater detail below, a charge vessel, manufactured from a polymer having suitable mechanical properties, is located in the skeleton casing. The polymer weighs less than traditional cartridge materials such as brass, thereby resulting in a reduction in cartridge weight.

Problems solved by technology

Gases from the ignition of the gunpowder, when contained, increase the pressure within the casing and cause it to expand.

As the casing expands, it seals against the wall resulting in a buildup of pressure in the casing.

Without sufficient springback, the casing would plastically deform, thereby hindering or preventing extraction of empty casings.

Cook off is especially limiting in automatic weapons, although semi-automatic weapons can also be affected.

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