Roller-delayed blowback (often called “roller-lock”) rifles radiate an aura of cool that defies logic and better judgement. It’s the reason why guys shell out more than $2,000 for a 9x19mm MP5 pistol clone that has all the practicality of a $400 MAC-10 pistol—it’s heavy, difficult to aim, and better with the addition of a buttstock. Sadly, to me, the MP5 has always been the coolest thing since sliced bread.
I say sadly because I’m far too pragmatic to purchase a pistol-caliber carbine for the great deal of cash modern clones go for—or the even greater deal of cash H&K-built carbines demand. Compared to carbines chambered in intermediate cartridges, 9x19mm models suffer from shorter range, less effective terminal ballistics, and pricy magazines.
Nonetheless, I needed to get my Navy SEALS “tacti-cool” fix while simultaneously satiating my pragmatic side. Thankfully, there is an inexpensive solution thanks to the Century Arms C93.
First, an important point. What is a roller-delayed blowback firearm? Basically, the breech is locked by two little wheels, or rollers, that protrude from the bolt. These protrusions fit two small cutouts in the chamber that cannot move under extreme pressure, and lock the bolt in place. Once internal pressure drops from escaping gases leaving the muzzle, the amount of rearward force is reduced sufficiently to allow the rollers to recede into the bolt body, thus unlocking the action.
Based on the Heckler & Koch HK33, the C93 is a roller-lock semiautomatic carbine chambered in 5.56mm. It feeds from aluminum, polymer, or steel-bodied box-type magazines in 100-, 40-, 30-, 25-, or 20-round varieties, and ships with one 40-round aluminum mag. As with most H&K roller-delayed designs, the C93 doesn’t hold the bolt open automatically when the rifle is empty. It’s not a deal breaker, but something to keep in mind.
The C93’s receiver is built from a single piece of folded steel welded together along the bottom, forming a shell that holds the fire control system, bolt, carrier, and barrel trunnion. Like an AK, the barrel is pressed into a forward trunnion. Unlike an AK, that trunnion isn’t either bolted to or milled from the receiver, but rather welded to it. This is a very secure method of doing so, but unfortunately, makes it non user-serviceable to the vast majority of shooters. Again, not a deal breaker. Most shooters will be content with the installed 16.25-inch barrel (with a 1:9 twist) that will offer everything they want from the gun without venturing into NFA territory.
Above the barrel are the iconic HK-style iron sights: a hooded post up front and a diopter drum at the rear. If that second part sounds confusing, you’re not alone. While immensely popular with gunmakers like SIG Sauer and Heckler & Koch, drum sights aren’t very common on other Western firearms. They consist of a canted hollow metal cylinder or drum, with holes drilled through it at various points each at a different height relative to the barrel. Each hole represents a different range setting assuming the lowest is zeroed properly. It’s effectively an adjustable A2 iron sight that somehow has four settings that can selected with a turn of the drum.
Other HK-specific novelties include the non-reciprocating charging handle located above the barrel. To load a magazine, the shooter retracts the charging handle and flips it up into a retention notch at the rear of the gas tube. Once a fresh mag is inserted, the shooter performs the super-cool “HK slap”—they backhand the charging handle loose from the notch, violently releasing the recoil spring’s tension, forcing the bolt into battery and chambering a round from the magazine.
Speaking of magazines, the one included is comically oversized for the carbine, but allows for uninterrupted fun for those of us who can actually afford to blow through 40 rounds of 5.56. The good news is that in testing the C93 ran with the cheapest ammo I could find, as well as military-grade M193 and M855 green tip. The only ammo brands that encountered any problems were 55-grain Winchester 3-Gun .223 and Hornady TAP 75-grain—both are my go-to rounds for serious work with .223/5.56mm carbines, and normally function without issue. I guess the C93 doesn’t have expensive tastes. Both rounds caused consistent failures to extract, while all others encountered zero issues—which is especially unfortunate, because the Hornady TAP and Winchester 3-Gun were among the most accurate rounds tested, performing just above one MOA at 100 yards. This was no easy feat given the scarcity of affordable optic mounts for the gun.
Most HK roller-delayed rifles, submachine guns, and carbines mount optics using a claw mount that engages the grooves in the receiver. It’s a very secure method, but like an AK requires a proprietary mount. Like all things HK, several of these mounts are collector’s items, fetching several hundred dollars. Chinese-made alternatives exist, but are not recommended as they tend to lose zero and require hand-fitting. Shooters should expect to pay around $60 for a quality optics mount.
Continuing rearward, the lower receiver and stock, like the handguard, are polymer and secured to the receiver by spring-retained push pins. The length of pull on the standard stock is a happy medium that fits the majority of shooters, and allows for nose-to-charging-handle-style shooting. M4 stock adapters are available, as well as telescopic HK wire stocks, which greatly increase the portability of the rifle without suffering from the ergonomic woes of the the underfolding AK stock—provided shooters utilize an aggressive forward cheek weld.
After firing 200 rounds of steel-cased Wartak .223 and Wolf Performance Ammo as well as 150 rounds of mil-spec Federal XM193 and XM855 I can safely say the Century C93 runs like a Swiss watch, provided it’s fed what it likes. Its tastes are decidedly blue-collar, so shooters looking to enjoy their carbine on the cheap won’t have to invest in buying premium or match-grade ammo to do so. This makes sense given its $869.99 MSRP, less than half the cost of an actual HK33. Shooters interested in buying one will be happy to know that street prices are often several hundred dollars less.
What do shooters get for their hard-earned dough? A more-than-combat-accurate, roller-delayed, semiautomatic rifle in a common, soft-shooting caliber. While not the most inexpensive option for shooters looking for a modern black rifle, the C93 is a relatively cheap fix for HK enthusiasts who can’t afford to drop $2,000 on a rifle that takes $80 factory magazines. It may have it quirks, but for shooters not heavily invested in an AK or AR-15, the C93 makes a fine alternative. It’s one that can serve as a range-plinker, home-defense carbine, or HK-inspired addition to their collection.
Images by Jim Grant