A rifle stock has a body defining a magazine well configured to closely and removably receive at least a portion of the magazine, the body including an actuation element proximate the magazine well, the magazine well being a passage defining an insertion axis, and the actuation element having an actuation surface portion angularly offset from the insertion axis, such that the cartridge retention element operably encounters and is moved by the actuation element upon insertion of the magazine. There may be a magazine having a body with an exterior profile sized to be closely and removably received in the magazine well, the body defining a central passage configured to receive a plurality of ammunition cartridges, the passage having an open upper end, a cartridge retention element attached to the body and movable between a first retention position, and a second released position.