Massive Firepower: The Beta C-Mag in 7.62mm
By Chris A. Choat

The Beta Company has been known for their “C” Mag ever since the mid to late 1980s. At the time, the magazine was advertised as holding an unheard of 100 rounds of 5.56mm or .223 ammunition. Since then there have been several attempts by other companies at producing a firearm feeding device that rivals or exceeds the Beta C-Mag. These have met with varying degrees of success. Some work and some don’t. The Beta Company has set the bar when it comes to high capacity feeding devices with their C-Mag, even being adopted by police and military units worldwide. The drum has the definite advantage of time saved when reloading. When these drums are used in a military environment, this may be the difference between life or death.

For those that may be unfamiliar, the Beta C-Mag consists of two 50-round drum magazines hooked together that feed a single “tower” in the shape of a standard magazine. The drums are spring driven and feed alternately from either side to produce a constant 100-round supply of ammunition. With the drums feeding from alternating sides the magazine does not become lopsided as it unloads. This is all done with a magazine that protrudes down from the bottom of the weapon in less space than a standard 30-round 5.56 magazine.

When the Beta C-Mag first came to market it was produced for one rifle system, the AR-15/M16. In later years different towers were produced allowing the C-Mag to fit other 5.55mm firearms. As their reputation for durability and reliability increased, manufacturers of other firearms wanted C-Mags to fit their guns. The Beta Company then started producing towers for other firearms in the 5.56mm family such as the Ruger Mini-14 and the Steyr AUG. Today, the 5.56mm C-Mag is produced to fit the AR-15/M16, the FN SCAR, the FNC, the H&K G-93/53 series, the H&K G-36 series, the SIG 550/551 rifles, the Royal Ordnance SA 80, the M-249 SAW, the H&K 416 series and the list continues to grow as other firearms are designed.

Not willing to rest on their past accomplishments, the Beta company next started producing their C-Mag in caliber 9mm between 1999 and the year 2000. This first 9mm C-Mag was made to fit the extremely popular H&K MP-5 submachine gun. Owners of this 750 rounds-per-minute gun were extremely happy because now they had enough ammunition for a burst that lasted more than a couple of seconds. The magazine quickly became a hit with the subgun competition crowd as well as some tactical units. The H&K MP-5 model was followed by drums for the Colt 9mm SMG, the Uzi and just recently by a new model that will even fit the 9mm Glock pistol. The Glock model is the perfect fit for owners of the select-fire Glock 18. The Glock 18 has a cyclic rate of around 1,200 rounds per minute and if a Beta C-Mag can keep ammo fed to this gun it can keep up with just about any gun. Now with several carbines designed to use the Glock magazine there is sure to be an extended market for these drums.

With C-Mag models for the 5.56 and the 9mm platforms, shooters started to ask the question, “What about a .308 version?” After all, it was the natural progression of things and the .308 AR platform was gaining in popularity. Whenever asking a Beta Company representative at past SHOT Shows that very question, the answer was always, “maybe, someday.” “Someday” has arrived and Small Arms of the World has received one of the first Beta C-Mags in 7.62 caliber. The drum is available in models to fit the AR-10, the FN-FAL, the H&K 91/G-3 series and also a model for the M1A/M-14 rifle. The drum we were sent for testing was for the H&K guns.

The first thing that you notice when unpacking the Beta C-Mag in 7.62mm is that it comes in an extremely well-made carrying case. The case is made from a very heavy black Cordura nylon and features a padded exterior. It also has a padded shoulder carry strap that can be removed via Fastex type buckles. The case has one exterior pocket that holds two tubes of dry graphite powder as well as a five-round personal loader. There is also an interior pocket that holds a very detailed user’s manual. There is no other way to put it; the drum is large – about twice the size of a 5.56 model. It is also heavy. The 5.56 C-Mag weighs a tad over 4.5 pounds loaded. The 7.62 version tops the scales at a whopping 10.5 pounds when loaded. With a magazine this heavy you have to have a very robust magazine catch to hold it in place. The H&K guns are definitely up to the task with strong steel magazine catches and heavy spring pressure required to release them. The drum was tested in four different H&K guns and there was no problem with the drum latching securely in the guns and staying in place until they were released. It should be noted here that the user manual states that a loaded drum should only be loaded into a gun with the bolt locked open. There is a lot of spring pressure on the last few rounds loaded into the drum and trying to lock one in place in a gun with the bolt in the closed position is futile.

Loading the drum is just like loading either the 5.56 or 9mm versions. The user manual says that the drums can be loaded either by hand, one round at a time, or with the included plunger type personal loader which allows loading five rounds at a time. Use the loader and save yourself a lot of time, not to mention your thumbs. To use the loader you simply snap it onto the magazines tower, raise the plunger, drop 5 loose rounds into a slot on the side of the loader and press the plunger down to transfer the rounds into the drum. Repeat this twenty times and the drum is loaded. The last ten to fifteen rounds require quite a bit of pressure to load but the loader is very well made and handles the task easily. The drum sent for testing has clear back covers installed on it and according to the Beta Company website that is the only way the .308 drums are available. There are now clear back covers available for all models allowing the user to tell at a glance how many rounds are left, which is very logical and useful.

The guns chosen to test the new drum were an H&K 91, an H&K G-3, an H&K Model 11 and an H&K 51. The H&K 91 is naturally semi-auto and the other three are select-fire. Ammunition used in the test was primarily military ball type but there is no reason that any quality 7.62 x 51 ammunition wouldn’t work. After loading the drum it was locked in place in the H&K 91 and the testing began. The drum proved boringly reliable firing over half of its contents without a hitch. The drum was then transferred to the H&K Model 11. For those that aren’t familiar with the Model 11, it’s kind of a cross between an H&K Model 21 belt-fed and the H&K G-3 magazine fed guns. It is magazine fed like the G-3 but it also has the quick-change barrel of the Model 21. The rest of the C-Mag was fired through the Model 11 on full-auto. The drum fed both guns flawlessly. The drum was again loaded and fired mostly full-auto through the Model 11 again without a hitch. Cyclic rate on both of these guns runs around 600 rounds-per-minute. The testers then switched gears, literally. The drum was once again loaded and this time locked into an H&K 51. The H&K 51 is not a factory model as it was never produced by H&K. The 51 is a G-3 that was shrunk down to the size of an MP-5. This tiny fire breathing firearm goes through ammunition at the rate of right around 1,000 rounds per minute. Again, the Beta C-Mag functioned perfectly. In all the first day of the test we ran over 500 rounds of ammunition though the drum and could not find a single problem in either loading or “unloading” it. The drum has since had another 500 rounds put through it and still it functions exactly as advertised.

In conclusion we found that the .308 Beta C-Mag is military tough and reliable just like the 5.56 and 9mm models. It feeds and functions with utter reliability and, unlike copycats, these drums work all the time no matter what. Another great feature of a Beta C-Mag is that it can be left loaded indefinitely without the springs taking a set. This is a definite advantage in the tactical arena. With a retail price of $470 complete, the new Beta C-Mag is not cheap; but then again quality never is.

The Beta Company
2137B Flintstone Drive
Tucker, GA 30084
Phone: (770) 270-0773
Fax: (770) 270-0599
Website: www.betaco.com
Email: cmag@betaco.com

This article first appeared in Small Arms Review SAW (May 2012)
and was posted online on March 30, 2012


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