US Patent 8689475 Firearms magazine for rifle length cartridges

A firearms magazine has compound tapered side walls and feed lips having substantially parallel end portions for maintaining contact with the cartridge as it is loaded. Removable inserts reduce the interior length and width to hold cartridges of different sizes. The insert has a channel along its height to protect the cartridge noses, and is held by a reinforcing member. A movable cartridge follower feeds the cartridges out of the magazine and has projections slideable in channels of the insert.