Magazine capacity has always been one of those things where a balance must be struck. In the military-rifle category, we’ve constantly seen an increase in the rounds carried. In WWI, it was five rounds, and in World War II, it was eight rounds. Vietnam saw the rise of the 20-rounder, and eventually, with the adoption of the M16, 30 rounds seemed just right. You’re always balancing capacity with size and weight, as well as the ability to shoot from cover and prone. With that in mind, there have always been people who’ve tried to go bigger, and a company called Beta tried to give the military a 100-round drum.


The Birth of the 100-Round Drum

Going from 30 to 100 seems like quite the jump, but the Beta C-Mag, or Century Mag, promised a drum magazine that would provide the ultimate source of fire superiority for a rifleman. The 100-round drum came to life in 1987 at an interesting time. Suppressive fire at the fireteam level was on the mind of the military collective, and the M249 SAW had just been adopted in 1985.

Even “light” machine guns are heavy compared to rifles. I’d imagine special ops dudes wanted a lot of firepower but a lighter weapon. Beta shopped the drum around to the DoD and Spec Ops community. A 100-round drum seemed interesting enough, and the military gave it a thorough run down in the early 1990s.

(U.S. Army)

The C-Mag featured a dual-sided design that looked like two drums connected at the center. The design allowed the drum to be compact vertically and store its bulk horizontally. Therefore, shooters could achieve a low prone without issue. Obviously, the gun would be quite bulky, and carrying an extra drum would be a task that required its own kit bag. Loading it required a tool and, on occasion, graphite to keep everything running smoothly.

Sadly, it failed, as drums often do. Drums are complicated, and magazines should be simple. Complicated designs are more prone to failure, and that became evident in the initial testing. After that, the Beta C-Mag went away… for a minute anyway.


Enter the GWOT

In the early stages of the GWOT, the Beta C-Mag saw another rise in popularity. Someone didn’t get the memo regarding what had happened during the testing in the 1990s, and Beta came knocking once more. It offered a new and improved C-MAG to the military once more, and it became an off-the-shelf purchase option for units deploying to Afghanistan. A unit known as the Rapid Equipping Force was buying them up and sending them out.

Courtesy Beta

I know what you’re thinking. What’s the point of a 100-round drum when units have belt-fed automatics? Well, keep in mind that getting these guns to troops is a slow process. For example, the SIG M17/M18 became the military’s new handgun in 2017, but the last Beretta rolled off the assembly line in September of 2021.

100 round drum Afghanistan
Courtesy Beta

In fact, up into the invasion of Iraq, there weren’t enough M249s in the hands of deploying Soldiers and Marines. Oftentimes the squads lacked firepower, especially in reserve National Guard units. As such, a 100-round drum could be loaded into a rifle and used to provide fire superiority.


Did It Work?

The Beta C-Mag deployed and saw action. It’s tough to say how many deployed and what problems soldiers saw with them. However, an article in Defend America News, written by Staff Sergeant Kevin Askew, portrayed the C-Mag as a piece of junk. The C-Mag failed over and over on a square range with little stress applied. Soldiers seemed to hate it and were quoted as saying, “I’ll stick to 30 rounds.”

KCI 100 round drum
KCI’s 100-round drum. (Courtesy of author)

The 82nd Airborne carried these drums into Kandahar, and they met failure after failure. Sadly, communication wasn’t great between military forces or even units. So the drums wouldn’t stop being purchased and issued.

The 100-round drum was also evaluated by the Naval Surface Warfare – Crane Division. Their evaluation showed they were not reliable and tended to fail at a very high rate. The testing done at Crane eventually resulted in a stop order sent out to prohibit the use of C-Mags for forward-deployed units.

That was the death of the 100-round drum… in military service anyway.


Where Can I Get One?

Beta still makes the C-Mag, and you grab one should you so choose. However, they are expensive as hell and not something I’d want to purchase. Especially with their reliability issues.

However, a Korean company called KCI still produces a clone of the Beta drum. It retails for a fairly lower price tag than the original. I’ve had one for a good bit now as a conversation piece.

KCI 100 round drums
KCI’s 100-round drum. (Courtesy of author)

On a flat range, it runs fine, but it’s not something I’d trust my life to. Nevertheless, the gun control industry seems to hate it, so I love it by default. For a little more than 100 bucks, you can have your own 100-round drum.