Editing Beta C-Mag (section)

==Design==
{{multiple image
| align     = right
| direction = vertical
| width     = 200
| footer    = Schematic illustration between a full and empty Beta C-magazine
| footer_align = center
| caption_align = center
| image1    = Double drum magazine filled.svg
| alt1      = Double drum magazine filled with 100 rounds
| caption1  = Fully loaded.
| image2    = Double drum magazine empty.svg
| alt2      = Expended
| caption2  = Empty.
}}

The C-Mag is a compact twin-drum magazine design that accepts up to 100 rounds of ammunition. It consists of two main components: the twin-drum storage housing and an interchangeable feed clip assembly. The storage housing is standard and fits any like-caliber weapon. The feed clip assembly serves as an adapter for the specific weapon.

Before loading and after firing, the feed clip is filled with spacer rounds that are an integral part of the magazine. The upper half of the top spacer round is tapered to allow the weapon bolt to close after the last round is fired. The length of the string-set depends on the customized feed clip for the individual weapon.

During loading, cartridges are inserted on top of the spacer rounds, through the feed clip and into the drums. The cartridge column splits at the juncture of the feed clip and the housing to distribute the ammunition evenly into the drums in two concentric rows.

During firing, spring-driven rotors advance the cartridges in both drums until they meet at a cam blade that merges the cartridges into a single column that feeds up through the feed clip and into the weapon.<ref>{{US Patent|4658700}}</ref>