Patent ID: 7854083

Claim:
A cartridge magazine comprising: a cartridge magazine box configured to form a housing of the cartridge magazine, the housing having an elongated channel configured to receive a plurality of cartridges in a single column, the cartridge magazine box formed from plastic so as to have inherent plasticity, a pair of retaining lips positioned on the housing, the retaining lips formed from a stiff metal, a follower operated by a spring, the follower configured to press a plurality of cartridges in the cartridge magazine to an upper position so that when in said upper position the topmost cartridge is ready for feeding into a chamber of a firearm and in said upper position the topmost cartridge rests against said pair of retaining lips, said retaining lips configured in cooperative engagement with said cartridge magazine box with its inherent plasticity so as to remain in a first position when the topmost cartridge is in the upper position, and configured to be operatively displaceable to a second position wider than the first position, wherein in said first position the distance between the retaining lips is less than the diameter of a cartridge case of said plurality of cartridges.