Drum Magazine
Drum magazines have a body defining an interior and having a rear wall, a rotor rotatably mounted within the interior of the body, the rotor having a periphery defining a plurality of cartridge-receiving spaces, the rotor positioned to define a rim path proximate the rear wall, such that rims of cartridges received by the rotor periphery are proximate the rear wall, and a first rim-engagement element within the interior of the body and proximate the rim path, such that the rims of cartridges passing by the first element are contacted to axially shift each cartridge with respect to a subsequent cartridge. The first rim-engagement element may be a raised protrusion on the body. The rims of cartridges passing by the first rim-engagement element may be contacted to actually shift each cartridge rearward with respect to a subsequent cartridge.
1 . A magazine for a firearm operable to receive rimmed cartridges, the magazine comprising:
a body defining an interior and having a rear wall;
a rotor rotatably mounted within the interior of the body;
the rotor having a periphery defining a plurality of cartridge-receiving spaces;
the rotor positioned to define a rim path proximate the rear wall, such that rims of cartridges received by the rotor periphery are proximate the rear wall; and
a first rim-engagement element within the interior of the body and proximate the rim path, such that the rims of cartridges passing by the first element are contacted to axially shift each cartridge with respect to a subsequent cartridge.
2 . The magazine of claim 1 wherein the first rim-engagement element is a raised protrusion on the body.
3 . The magazine of claim 1 wherein the rims of cartridges passing by the first rim-engagement element are contacted to axially shift each cartridge rearward with respect to a subsequent cartridge.
4 . The magazine of claim 1 further comprising:
a second rim-engagement element within the interior of the body and proximate the rim path, such that the rims of cartridges passing by the second element are contacted to axially shift each cartridge with respect to a subsequent cartridge.
5 . The magazine of claim 4 wherein the second rim-engagement element is a raised protrusion on the rear wall.
6 . The magazine of claim 4 wherein the rims of cartridges passing by the second rim-engagement element are contacted by the second element when the rim of a subsequent cartridge passing by the first rim-engagement element is contacted by the first element.
7 . The magazine of claim 4 wherein the rims of cartridges passing by the second rim-engagement element are contacted to axially shift the each cartridge forward with respect to a subsequent cartridge.
8 . The magazine of claim 1 wherein the cartridge-receiving spaces in the rotor are spaced apart to position the rims of the cartridges so the rims are free to move forward and rearward with respect to one another.
9 . The magazine of claim 1 wherein the center to center spacing of the cartridge-receiving spaces is greater than the diameter of the rims of the cartridges.
10 . The magazine of claim 1 wherein the cartridge-receiving spaces in the rotor position a forward portion of the cartridges to the right of the rims of the cartridges.
11 . The magazine of claim 1 wherein the rear wall is a removable cover.
12 . The magazine of claim 1 , further comprising an arcuate guide plate mounted within the interior of the body.
13 . The magazine of claim 12 , wherein the guide plate guides the cartridges upwards as the cartridges engage the guide plate.