Diemaco (Colt Canada) Polymer Magazine
As early as the 1980s, several attempts had been made to make a reliable magazine out of polymer. Early efforts produced brittle magazines that were unreliable, as they were far more fragile than the aluminum magazines. The first successful attempt was by the Canadian firm Diemaco, now called Colt Canada. Development went poorly at first, as the units were rejected by the Canadian forces in favor of aluminum magazines. Not long after that, Diemaco completed the design and worked out all the bugs, producing the first combat-reliable synthetic magazine.

These Canadian polymer units are identified by the maple leaf on either side and should not be confused with aftermarket look-alikes. Diemaco has sold them to other military forces, including Denmark and the Netherlands. They have been used in many theaters of operation throughout the world. It’s unfortunate they are unavailable commercially in the United States, although some find their way here.

I have had several opportunities while visiting Colt Canada (Diemaco) to test its arms with these magazines and have had success every time. I have not experienced any malfunctions. These magazines were worth mentioning because of the pioneering work on Diemaco’s part in making the first successful polymer magazine for the AR rifle.

Beta Company C-MAG
The Beta Company was incorporated in 1983 and entered into an agreement with Leroy James Sullivan for the development of a higher-capacity magazine the same year. Sullivan was the designer of the 100-round C-MAG magazine, and he assigned all rights, title and interest in the C-MAG invention to the Beta Company in 1983. Sullivan made a metal prototype of the C-MAG, but there were no development or production activities until 1985. Starting in 1985, the C-MAG was developed by Beta engineers with only minimal initial input from Sullivan.

Production of the dual-drum, 100-round C-MAG for the M16 started in 1987. Through the years Beta made refinements, including changes in plastic material used for the drum housing to improve durability, variations in drum clip strap attachment to improve impact resistance, removable covers for easier disassembly, adjustments in the feed clip, the addition of linked spacer rounds for easier maintenance, and clear covers.

The C-MAG has served throughout the world. It is most effective in guns such as the Colt LMG and M4A1 with the heavy SOCOM barrel. The magazine is also best used like the Soviet drum magazines in defensive postures. Due to the way the cartridges rest in the drum they make a lot of noise when walking, running or moving. The drum I tested functioned flawlessly in a Colt M4 carbine.

Magpul PMAG
Although Magpul is a new company, it has created quite a name for itself with its polymer magazine, the PMAG. At the 2007 SHOT Show, factory reps were throwing them on the ground, stomping on them and grinding the heels of their boots into them to demonstrate the product’s durability.

An innovative feature of the PMAG is a cover that fits over the top of the magazine. It protects the feed lips from damage and dirt and, most importantly, when installed, pushes downward on the top cartridge, releasing tension against the feed lips. The benefit is long storage life for a fully loaded magazine. The cover can also serve as a feed lip gauge to determine if the lips are damaged. The PMAG 30-round magazine is designed for easy insertion into a rifle with a closed bolt. Some magazines are so stiff on the 30th round that it is difficult to insert the fully loaded magazine in the rifle. The PMAG also has a proprietary magazine follower that is 100-percent anti-tilt. Magpul has also introduced 20-round PMAGs in all the same colors as the 30-round counterparts, although they are not offered with the anti-tilt Maglevel system.

Currently, there are three different versions. The first is the standard PMAG, which is a solid color—the newest version permits the cap for the magazine to be attached to the base of the magazine. The second model includes the Magpul Maglevel system with two witness windows showing the number of unfired cartridges. When the orange mark on the magazine spring is visible in the top of the window, it is either empty or near empty. The third offering is called the EMAG or Export Mag, which has some design changes to the body to make it a more universal magazine with European arms that do not use the U.S. mil-spec magazine well, including the HK416, SA80 and Beretta rifles. It has a smooth exterior with one window on the left side, and it works perfectly well in the AR-15. MagPul offers its PMAG and EMAG in black, foliage green, olive drab, tan and orange.

MagPul PMAGs are the only magazines in my range bag and tactical gear. I cannot count the number of rounds that I have put through the magazines. The magazines have been in multiple rifles and I have never experienced any failures of any kind. PMAGs are in service throughout the world, including Iraq and Afghanistan. They’re gaining an incredible reputation for their combat reliability; many soldiers appreciate them and the potential exists for the PMAG to be the next standard-issue magazine for the U.S. military.

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