Abstract: A non-detachable magazine configured to be used for new manufacture of firearms or configured to replace a detachable magazine of an existing firearm is disclosed. The magazine may be pivotally mounted on a firearm using a hinge pin, allowing the feed end of the magazine to enter and retreat from the magazine well of the firearm. The magazine includes a magazine body and at least one arm connecting the magazine body to the hinge pin. In some embodiments, a firearm can be made compatible with the disclosed non-detachable magazine such that removal of the magazine is tantamount to disassembly of the firearm, and/or removal of the magazine renders the firearm inoperable.

Abstract: A detachable box magazine for firearms includes a hollow magazine tube extending longitudinally along a median plane. The magazine tube defines a single-stack portion extending to an upper tube end with an upper tube opening. The magazine tube defines a double-stack portion positioned below the single-stack portion and extending to a bottom tube end with a bottom tube opening. For example, opposite lateral margins of the front sidewall can have a stepped shape between the upper tube end and the double-stack portion. The rear sidewall can have a linear taper between the upper tube end and the double-stack portion.

Abstract: A detachable box magazine for firearms includes a hollow magazine tube extending longitudinally along a median plane. The magazine tube defines a single-stack portion extending substantially to an upper tube end that defines an upper tube opening. The magazine tube has a double-stack portion positioned below the single-stack portion and extending to a bottom tube end. For example, front portions of the opposite tube sidewalls have a stepped shape between the upper tube end and the double-stack portion, and the rear portions of the sidewalls have a linear taper between the upper tube end and the double-stack portion.

Abstract: A detachable box magazine for firearms includes a hollow magazine tube extending longitudinally along a median plane. The magazine tube defines a single-stack portion extending to an upper tube end with an upper tube opening. The magazine tube defines a double-stack portion positioned below the single-stack portion and extending to a bottom tube end with a bottom tube opening. For example, front portions of the opposite tube sidewalls have a stepped shape between the upper tube end and the double-stack portion, and the rear portions of the sidewalls have a linear taper between the upper tube end and the double-stack portion.

Abstract: A magazine for rimmed cartridges includes a magazine tube having first left and right ribs on an inside of the magazine tube extend inward from a forward portion of opposite sidewalls and are laterally spaced by a first spacing. Second left and right ribs on an inside of the magazine tube extend inward from a rear portion of opposite sidewalls and are laterally spaced by a second spacing that is greater than the first spacing. When the magazine is filled to capacity with rimmed cartridges, cartridges in the magazine are arranged in two offset columns with projectiles of the rimmed cartridges laterally spaced from a median plane by a first distance and rims of the rimmed cartridges laterally spaced from the median plane by a second distance that is greater than the first distance. Also disclosed is a baseplate that attaches to a magazine tube using a snap fit.

Abstract: A multi-caliber automatic rifle (AR) magazine is configured to alternately receive a first cartridge having a first caliber and a second cartridge having a first caliber. The multi-caliber AR magazine includes a first pair of ribs, a second pair of ribs, and a third pair of ribs such that the first pair of ribs and the second pair of ribs are configured to both support the body of the cartridge when loaded in the magazine. The second pair of ribs are indented toward a center of the multi-caliber AR magazine housing more than the first pair of ribs such that a distance between the second pair of ribs is less than a second distance between the first pair of ribs. The third pair of ribs can be rebated to form a dual-curved rib having a central convex portion connected between two concave portions.