Review: LWRC Six8 PDW

This article originally appeared in RECOIL Issue 11

Photography by Henry Z. De Kuyper

The Empire Called. It Wants Its PDW Back.
Hokey Religions and Ancient Weapons Are No Match for a Good Blaster at Your Side, Kid

Have truer words ever been spoken? Mr. Solo sure knew what he was talking about. Look past the killer custom Cerakote job, and you’ll see LWRC’s take on what a personal defense weapon (PDW) should be. This is the civilian version of the sub-carbine purchased by the Saudis for internal security purposes. And it rocks.

Over the past decades, the submachine gun has fallen out of favor for second line troops, and the PDW’s star is ascendant. The requirement to arm cooks and bottle washers with an adequate firearm that is smaller, lighter, and generally less capable than the standard-issue infantry rifle has led to some interesting developments. FN introduced the P90, which has seen limited international sales. H&K’s interpretation, the MP7, has found favor with troops that fall outside of its original intended audience. For example, SEAL teams have been employing it in raids on Al-Qaeda franchises in sub-Saharan Africa, due to its reliability, compact size, and controllable nature. And yes, I did just say “MP7.” Get over it.

As its name implies, the Six8 chambers 6.8 SPC rounds, which ballistically exceeds that of the 5.56mm.

Both firearms utilize a scaled-down cartridge, relying on extended magazines and full-auto capabilities to put enough lead on target. LWRC took a different approach. In conjunction with ATK Federal, who optimized the 6.8 SPC round for use in short barrels, the Maryland company came out with the Six8 IC-PDW, which offers rifle-level ballistics from a very compact package.

Saudi Arabia sits at the crossroads of an extremely volatile neighborhood. While its politics may be decidedly antiquated by Western standards, it remains a key ally in the region, the loss of which would be disastrous for U.S. foreign policy. Following numerous attacks by domestic and foreign terrorist groups, the Saudis decided to get serious about their internal security forces (and drag them kicking and screaming out of their traditional, largely ceremonial role), putting them to serious work. Let’s face it, when your issued weapon is a gold-plated MP5K, there’s going to be chuckling whenever you walk into the room.

The replacement for the aforementioned MP5 is the Six8. While not exactly a sawed-off elephant gun, its ballistics exceed that of a 5.56mm by a substantial margin. As evidenced by bruises left on my shoulder from range time, this thing has a decent thump on both ends. And while I wouldn’t volunteer to stand down range of any of the PDW cartridges, there’s no way in hell I’d go forward of the muzzle of this beast. Launching a 90-grain bonded softpoint at 2,400 feet per second (fps), it’s like the Tasmanian Devil of SBRs.

Details, Details…

The LWRC team has managed to pull off an impressive feat of engineering. Not only have they shrunk the AR to very compact dimensions, they also made it run reliably with a bigger round. To achieve this, they ditched the direct impingement operating system in favor of a short-stroke piston housed under the handguards. The usual recoil spring and buffer located in the butt have been redesigned. The buffer is now part of the bolt carrier and, in addition to being reduced in size, contains a second, auxiliary spring and sits inside the rear of the carrier. This has the effect of absorbing some of the force as the assembly impacts the end of the chopped-down buffer tube. The main recoil spring has been swapped out for one made from flat wire, rather than the round stock typically found in the AR platform, in order to reduce the amount of space it takes up when compressed.

The abbreviated receiver extension is achieved via a small buffer that sits inside the bolt carrier, a flat wire action spring, and a second auxiliary spring. The hobbit-sized buttstock telescopes open and closed.

The gas system itself is a modified version of the one found on their full-size guns. It comprises a fixed piston that is part of the gas block, a movable cylinder which slides over it, a spring-loaded operating rod and a short connecting rod which bridges the gap between cylinder and op rod. The gas block’s location is dictated by the length of the cylinder and op rod, which no doubt caused some head scratching regarding gas-port diameter, as pushing it this close to the muzzle reduces dwell time considerably. That the gun functions as well as it does is a testament to the amount of development work by LWRC’s engineers.

Because of these changes, the field stripping procedure is decidedly non-standard. To tear down the gun, you first clear it and then punch out both takedown pins. In order to separate the upper and lower receivers, you have to pull out the recoil spring which is wound around the rear of the buffer (itself attached to the bolt carrier) as the upper and lower come apart. Although the process is considerably more involved than a regular AR, the good news is that the carrier and bolt stay much cleaner due to this being a piston-operated gun.

Now that the upper and lower are apart, you can turn your attention to the gas system. Unscrew the two knurled and slotted thumbscrews at the front of the handguards. The upper section of the free-float tube can then be slid forward and off, revealing the gas system beneath. Push back on the op rod and remove the connecting link. Slide off the gas cylinder and pull the op rod free of the upper receiver. You can now scrape carbon from the piston exterior and out of the cylinder before reassembling in the reverse order.

The Six8’s lower receiver is hogged out of bar stock and features some neat touches. Fully ambidextrous, the right side has a mirror image bolt hold open, which means that the user can lock open the action without having to shift his grip. This is a major improvement when it comes to dealing with stoppages, as the firing hand can remain on the pistol grip while the support hand racks the charging handle and administers the “tactical tickle.” An ambi mag catch and safety complete the controls, while making the gun louder is governed by a proprietary trigger and hammer, both of which are coated in nickel Teflon.

The abbreviated stock slides in tubes machined into a lower receiver extension and is held in either the open or closed positions by a right-side button detent. In order to make the package as compact as possible, the postage stamp-sized butt plate telescopes over the end of the buffer tube. The butt plate itself is nicely machined with grooves on its rear surface and is about as small as it could be and still fulfill a useful purpose.

Folding iron sights adorn the continuous upper Picatinny rail and are a work of art in themselves. Made in-house from 7075 aluminum and type III anodized, they’re dehorned and lock in the deployed position. Two sizes of aperture are available on the rear sight, by means of twisting a square post, which is adjustable for windage. Elevation adjustments are handled on the front sight. Another proprietary component is the beefy, ambidextrous charging handle, which features twin, independent latches on either side.

Moving toward the business end, we find a folding vertical foregrip. While not usually a fan of VFGs, on smaller guns they serve the useful role of a hand stop, preventing the shooter’s support hand from straying too close to the muzzle. They also keep exposed flesh away from the barrel and gas system as they heat up — this was obviously a consideration for LWRC, as they’ve fitted insulating panels on either side of the handguard.

Rounds Downrange

It’s generally accepted that M855 ammo requires an impact velocity of 2,500 fps in order to fragment — below this velocity floor, the bullet simply drills a 0.22-inch-diameter hole in flesh. An 8-inch barreled AR typically delivers a muzzle velocity of around 2,340 fps, leaving us behind the eight ball from the get-go. This performance can be improved through the selection of a better bullet, but it’s illustrative of the problems faced by our troops and the limitations of 5.56 in general. The 6.8, on the other hand, gives us a bigger, heavier bullet, moving at higher velocity. And what’s not to like about that? In addition, the Federal round issued with the Saudi weapons uses a bonded softpoint that should give excellent intermediate barrier penetration and terminal performance, far exceeding that of other PDWs.

At the range, the difference between 5.56 and 6.8 SPC was very evident. There’s no such thing as a free lunch, however, so the increased smackdown offered by the 6.8 is countered by increased recoil and split times. The usual method to mitigate recoil would be to mount a brake, but with the muzzle this close to your face, you’d regret that decision in short order. Instead, the Six8 is offered with a four-prong flash hider, which also provides a mounting point for a dedicated suppressor currently in development.

If you use a bladed, traditional stance then this little gun probably isn’t for you. Even with the stock extended it’s too short to use effectively, and in the collapsed position it lends new meaning to the phrase, “nose to charging handle.” Tuck it in close to your centerline, however, and it works just fine — though you’re not going to want to burn several hundred rounds in one session, as the butt plate concentrates recoil into a pretty small area. Target transitions are extremely quick and the stock trigger, though quite heavy at about six pounds, breaks cleanly.

While time constraints didn’t allow us to put the Six8 through the wringer, we burned enough ammo to come away with a favorable impression. As a means of packing heavyweight ballistics into a tiny space, it’s a very competent solution. The Imperial High Command would be proud.

Visit https://www.lwrci.com

A Fresh Mag

The most failure-prone component of most small arms is the magazine. In designing the Six8, a hard look was taken at the magazines available for it and most of them came up short. While 5.56mm mags can be used in a pinch, the larger diameter of the 6.8 SPC round usually causes feeding problems. Dedicated 6.8 mags are almost always made from steel, as this allows thinner material to be used for the tubes, increasing their internal dimensions. The Saudis, however, looked at Magpul’s offerings and said, “We want that.” And when you can slap a bunch of petrodollars on the table, people tend to listen.

To accommodate the bigger cartridge, the magazine has been stretched. Due to the thicker walls needed to provide adequate strength when dealing with polymer, they are noticeably larger when you pick one up. As a result, the Six8’s magwell no longer accommodates standard USGI mags. While this may be considered a drawback from an interchangeability standpoint, the tradeoff is that the magazine is optimized around the case it’s supposed to feed. As LWRC’s Joe Devens put it, “We basically designed the gun around the magazine — both lower and upper have been changed to fit the 6.8 round. Magpul’s help was a huge benefit to us.”

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