A cartridge handling apparatus includes cartridge storage magazines which define cartridge storage slots therein. A projecting element positioned on a back inside wall of each of the storage slots of the storage magazines fits into a recess in the cartridge when the cartridge is oriented in a proper orientation so as to permit the cartridge to be fully inserted into the storage slot in the proper orientation. The projection prevents full insertion of the cartridge in the cartridge storage slot when the cartridge is not in the proper orientation. By changing the orientation of the projection, the storage slot accepts cartridges in a different orientation as the proper orientation. A snap lock is provided on each of the storage slots to engage the cartridge when fully inserted therein. 12