In March, Tango Down introduced a new polymer AR-15 magazine called the ARC-L. Tango Down took a different approach to the AR-15 magazine, and designed something new that is worth looking at.
Tango Down developed the ARC-L magazine by going back to the drawing board and taking a hard look at ammunition feeding in the AR-15 platform. Tango Down started with the understanding that 30-round magazines in the AR-15 are curved, yet the magazine well in the AR-15 is straight.
Instead of utilizing a single piece of molded plastic, the Tango Down magazine is a two-part assembly that snaps together (permanently) in the middle. There are several reasons for this, but the main one is to have a straight portion that is in the magazine well, with a curved portion that is the part extending beyond the magazine well.
Tango Down says by using the two-piece construction they can mix various polymers for different portions of the magazine:
We can also mix materials, impossible with conventional plastic magazines. We can offer transparent lower/high tensile strength upper sectioned magazines that avoid the brittle feed lip issue of all-transparent material construction.