Jam resistant ammunition magazine
Methods and apparatus are provided for a passive locking device for preventing an ammunition belt from sliding across the top of an internal wall of an ammunition magazine used in conjunction with a belt feed weapon. In one embodiment the passive locking device is movable between a locked position in which a locking end is in close proximity to the top of the internal wall, and an unlocked position in which the locking end is spaced apart from the top of the wall.
1. An ammunition magazine for storing a continuous belt of linked ammunition rounds and dispensing the ammunition to a belt feed weapon, comprising:
an elongated box comprising an ammunition compartment bounded by walls;
an opening in the box for dispensing the belt of linked ammunition; and
an ammunition lock proximate the opening comprising a guided slide member with a locking end, the guided slide member adapted for longitudinal sliding movement between locked and unlocked positions in a direction substantially perpendicular to the plane of an ammunition compartment wall, wherein in the locked position the distance between the locking end of the ammunition lock and a top of the ammunition compartment wall is less than the thickness of the ammunition belt, and in the unlocked position the distance between the locking end of the ammunition lock and the ammunition compartment wall is greater than the thickness of the ammunition belt; and
a spring configured to bias the guided slide member from the unlocked position to the locked position.
2. The ammunition magazine of claim 1 , wherein the locking end is a cylindrical roller journaled for rotation about an axis substantially parallel with the top of the ammunition compartment wall.
3. The ammunition magazine of claim 2 , wherein the ammunition compartment wall is a first crossover wall dividing the elongated box into a first ammunition compartment extending from the crossover wall to a back wall of the ammunition magazine, and a crossover bay between the crossover wall and a front wall of the ammunition magazine, and wherein the ammunition lock is positioned above the ammunition compartment, and slides forward, toward the crossover wall to the locked position.
4. The ammunition magazine of claim 3 further comprising:
a first longitudinal partition dividing the elongated box into adjacent first and second ammunition compartments extending from a back wall of the box at one end to respective first and second crossover walls at the other end; and
a second ammunition lock associated with the second ammunition compartment.
5. The ammunition magazine of claim 4 , further comprising a feeder chute atop a lid, the feeder chute comprising a chute top, a chute floor, and opposed chute sidewalls, wherein the ammunition locks are mounted between the lid and the chute floor, and the opening is in the lid.
6. The ammunition magazine of claim 4 , further comprising a second longitudinal partition dividing the box further into adjacent first, second, and third compartments extending from the back wall at one end to respective first, second, and third crossover walls at the other end.
7. The ammunition magazine of claim 6 , further comprising baffles subdividing the ammunition compartments into ammunition bays.
8. The ammunition magazine of claim 4 , wherein the top of each of the crossover walls comprises flange portions at the sides of the crossover wall projecting above a top edge between the flange portions, creating a notched shape.
9. The ammunition magazine of claim 8 , wherein the distance between the locking end of the ammunition lock and the top of the flange portions is less than the thickness of the ammunition belt when the ammunition lock is in the locked position, and greater than the thickness of the ammunition belt when the ammunition lock is in the unlocked position.