The LWRC Piston-Operated Carbine

Rochester Police Department Emergency Task Force Operator Henry Favor test fires the LWRC M6A1 rifle. The rifle is equipped with the Magpul CTR Stock, MIAD grip and PMag magazine. The optic is an Insight Technology ISM-V combination red dot and laser and M3X tactical illuminator with its pressure pad mounted on a Knights Armament Company vertical pistol grip. The rear sight is the GI issue MaTech BUIS.

LWRC (Land Warfare Resources Company) began as Leitner-Wise Rifle Company.  The company was a research and development firm dedicated to making large bore direct impingement M16-type rifles.  The rifle was chambered for the large .499 LWRC cartridge, which gained the interest and a developmental contract by the U.S. Coast Guard.  In an attempt at making the .499 more reliable, a short stroke gas piston system was developed; its basic architecture similar to the WWII G43.  That was not enough to produce a reliable large bore rifle as the large bore straight walled .499 cartridge was not optimal for feeding or extraction reliably in the M16 receiver.  Mid development, the company was faced with a dilemma.  There was no future military use for large bore cartridge M16 but saw huge potential in applying the operating system to the NATO standard M4 5.56mm carbine.  The company had to figure out a way to introduce something different than the standard rifle.  Around this time (early 2000), Heckler & Koch began showing their HKM4, now their 416 weapon system – a piston operated version of the M4 carbine.  This is basically an AR18 type piston system.  Heckler & Koch concentrated on military and law enforcement sales and decided not to serve the commercial market with their piston-operated rifle.  LWRC would not dismiss any potential market or customers.  Several prototypes later, they had working rifles.  The goal was not to re-invent the wheel and change the entire M4 Carbine, but to make the M4 work cleaner and more efficiently and make it more reliable in adverse conditions.  The company was about to go through a major change from an R&D company, to a firearms manufacturer.  The company was bought in a management buyout in early 2006 and the company changed the way they conducted business.  The company name would remain LWRC, but to reflect the change in management the company would be known as Land Warfare Resources Corporation.  In the spring of 2008, LWRC was having difficulty meeting the explosive demand for their rifles.  LWRC sought a partner familiar with mass manufacturing for large and small government orders.  Majority share of the company was sold to RifTech in an asset buyout.  RifTech is a company whose same shareholders own MaTech and several other significant defense product manufacturing companies on the eastern shore of Maryland.  LWRC also added International to their name to reflect their efforts to manufacture for allied countries.  The new CEO, Mr. Richard Bernstein, former CEO of L3 Communication’s Aerospace division, brings the experience and leadership required to take the company to the next level.  Moving forward, the new team at LWRC International feels this partnership between the design and development crew at the old LWRC and the manufacturing experience of the new crew will give the company a competitive edge with potential U.S. and foreign government contracts.

The test and evaluation rifle was fired more than 1,500 rounds. The rifle is equipped with Magpul CTR Stock and MIAD grip. The optic is a Insight Technology ISM-V combination red dot and laser and M3X tactical illuminator with its pressure pad mounted on a Knights Armament Company vertical pistol grip. The rear sight is the GI issue MaTech BUIS. The magazines are coupled Lancer L5 translucent magazines.

LWRC has been actively competing for weapons contracts.  As of this writing, LWRC is entering a submission into the Marine Corps Infantry Automatic Rifle (IAR) program.  This is a highly modified version of their proven piston system with the addition of a closed bolt semiautomatic operation and an open bolt fully automatic operation.  They will undoubtedly be challenged by Colt Defense, Knights Armament Company, FNMI and H&K.  Their rifles are seeing use in all three markets (commercial, law enforcement and military).  Their piston system is not unlike any other piston operated firearm.  A short-stroke tappet system uses an operating rod that impacts the face of a highly modified carrier key to drive it rearward.  Then the operating rod would reciprocate back into the receiver.  What is truly unique about the LWRC system is how it releases excess gas from the moving piston.  The HK416 bleeds excess gas out the front of the gas block with a valve.  The Colt LE1020 bleeds gas from the sides.  The LWRC vents it under the handguard.  The piston itself directs the excess gases forward preventing any gas from getting near the receiver and bolt group while the operating rod pushes rearward, strikes the carrier key retracting the bolt.

The LWRC system can retrofit an existing impingement gun as well as they make many different rifles of their own.  With their own rifles, they use some of the most high-speed accessories to enhance their weapon. They provide the Magpul CTR stock and MIAD adjustable pistol grip.  They are provided with Magpul PMags, which are a synthetic magazine that might just be the most durable and reliable M16-type magazine on the market.  The rifle looks very much and feels like an issue M4.  In fact, the lower receiver is the same.

Shown is the top rail with the two captive pusher screws unscrewed.

The three sample LWRC rifles have excellent fit and finish.  They were equipped with Magpul CTR stocks (6-poition), enhanced trigger guard and MIAD grip.  The safe and fire position was ambidextrous and used hieroglyphic marks similar to H&K.  The LWRC piston guns all use the H2 buffer (2 tungsten and 1 steel weight) that are the same weight as a standard rifle buffer.  Two rifles each came with a 2-stage match trigger and the third used the standard trigger group.  Controls are identical to any other GI M16/M4 family of weapons.  The M6A2 rifle was provided with the proprietary LWRC olive green anodized receivers, MIAD pistol grip and CTR stock.

Three of the sample rifles had the LWRC monolithic Rail Adapter System upper receiver with quad Mil-Std 1913 rails.  The top rail is removable by two set screws on the face of the rail to enable access to the operating system for maintenance.  Like the standard rifles, the M6 series of carbines have a forward assist, fired cartridge case deflector and ejection port dust cover.  The M6 and M6A1 use standard front sight bases.  The M6A2 is basically the same as the M6A1 with the major change being to the barrel and handguard.  The standard front sight assembly is removed in favor of a low profile gas block and the handguard/rail extend past the gas block giving additional length of available rail for mounting accessories.  The M6A2 model utilizes a folding front sight.  The M6 rifle has standard M4-type removable two piece handguards.  The M6 rifle looks nearly identical to that of the standard M4 carbine.  As of the 2008 SHOT Show, several manufactures are introducing rail systems that can be used with either the standard gas tube or the various piston operated weapons.  This would be the LWRC equivalent to the standard issue M4 carbine.  One M6A1 rifle was equipped with a Canadian hammer forged 15.9 inch SFW barrel, Trijicon ACOG sight with a mounted red dot sight.  The back-up sight was the Government Issue MaTech BUIS.  The M6A1 rifle used for test and evaluation was equipped with a 16-inch heavy barrel in the free floating LWRC M6A1 upper receiver.  The accessories used on the rifle were an Insight Technology M3X flashlight with a pressure pad activation mounted to a Knights Armament vertical pistol grip, Insight Technology ISM-V red dot/laser sight module and a LaserMax UniMax green laser sight.  The fully automatic testing was conducted with this rifle’s upper receiver placed on a Colt M4 lower receiver equipped with a Magpul UBR stock and a H2 buffer.

Top rifle is the basic M6 rifle. This model is their basic M4-style rifle using a standard M4-type upper receiver, handguards and front sight base. The middle is the M6A1 rifle. This is the model that utilizes the LWRC proprietary free floating rail system but retains the standard rifle front sight base. The bottom rifle is the M6A2 rifle that uses a cut down gas bloc with a extended rail system.

The bolt carrier has a similar look to the standard M16 but with some changes.  First to notice is the carrier key is totally different.  The key on the LWRC bolt carrier is hardened super alloy and locked in place by a dovetail fit.  The rear of the carrier is flared outward leaving a larger diameter at the rear than the rest of the carrier.  The purpose of this is to keep the carrier in alignment with the buffer extension.  Due to the use of a piston, when the carrier is struck and it begins to move rearward, it is also moving on a slight downward angle.  The flare aligns the carrier with the buffer extension and prevents any damage to the buffer extension from the bottom edge of the carrier.  The interface between the piston rod and carrier key is mated with a beveled face of the carrier key and a rounded profile of the piston rod.  This keeps the piston rod centered at the moment of impact with the carrier key.  Also noted is the removal of the gas exhaust ports.  Due to this being a piston system, there is no gas to be bled off.  This also will prevent any dirt from entering the inside of the carrier.  Originally, the carriers were black and coated with a DuPont Teflon finish.  As of April 9, 2007, LWRC changed to a Teflon Nickel coating that is matte gold in color.  This finish has excellent lubricating properties and is more durable than the previous DuPont Teflon coating.  For $29.95 and a return of your black carrier, LWRC will send you out a new carrier with the updated finish.

LWRC has also introduced a new bolt for their family of weapons.  The LWRC Advanced Combat Bolt looks similar to the Lewis Machine and Tool Enhanced Bolt but with a few changes.  Like the LMT bolt, the LWRC Raptor extractor has a “lobster tail” appearance with dual buffered extractor springs.  There are no undercuts on the lugs adjacent to the extractor.  The bolt is manufactured from “Unobtanium” (i.e., proprietary metal LWRC does not want you to know about).  The bolts can be used in standard direct gas/impingement guns as well.  The bolts from LWRC all use gas rings.  The purpose is ease of assembly and it keeps the bolt in good alignment with the barrel extension.

LWRC M6A1 rifle equipped with a Canadian SFW barrel. Notice the Magpul CTR stock, MIAD grip and PMag. The rifle is equipped with a Trijicon ACOG rifle scope, MaTech BUIS and a SureFire tactical flashlight hooked up to a pressure pad mounted to a vertical pistol grip.

LWRC offers a wide variety of barrel lengths including 8, 10.5, 14.5 and 16.1 inches.  All rifles feature the M4-type extended feed ramps on the barrel extension as well as the upper receiver.  Both civilian/law enforcement semi-auto only as well as selective fire rifles are available.  LWRC sells the rifles in both black and flat dark earth colors.  The M6A2 DMR (Designated Marksmanship Rifle) is a match grade rifle equipped with either a Magpul PRS (Precision Rifle Stock) or a UBR (Utility Battle Rifle) stock.  The barrel is match grade and comes in 16 and 18 inches in length and to add to the solid feel of the rifle, the Magpul MIAD pistol grip and Enhanced Trigger Guard.  The trigger is upgraded to a Rock River two-stage match trigger.  This model is offered in 5.56x45mm as well as 6.8 SPC.

The M6, M6A1 and M6A2 are offered with an array of barrel lengths suited for nearly any combat scenario.  With the market place being what it is, the LWRC rifles can literally have most any design update, BUIS, optic, flashlight, pistol grip and stock enhances and trigger upgrades as that of the standard M16 and M4 carbines.

All the test rifles functioned flawlessly without lubrication.  The M6A1 rifle was fired more than 1,500 rounds.  More than half was fully automatic fire.  The accuracy was up to par with any M4-type carbine and the overall system was flawless.  Three Beta C-Mags were fired to test reliability.  All three magazines were fired in a single 100-round burst.  Again, the rifle functioned flawlessly.  During testing it was a conscious decision not to use lubrication as this author believes the Teflon Nickel coating of the bolt and carrier significantly enhanced the performance without lubrication.  The finish on the bolt carrier made only a rag necessary to clean it.  It has been my experience that piston operated versions of the M16/M4 weapon system experience slightly sharper recoil than the direct gas guns and the LWRC guns were no exception.  This sharper recoil is the result of the piston striking the top of the carrier key and that pushes downward on the bottom rear of the bolt carrier.  This changes the felt recoil of the normal in-line construction of the direct gas guns.  With the direct gas guns, the recoil energy is distributed evenly in the rear of the inside of the bolt carrier driving in rearward in line with the buffer and the shooters shoulder.

The M6A1 upper receiver (top) and the M6A2 upper receiver (bottom).

Noted arms expert, trainer and former Delta Operator Larry Vickers endorses the LWRC family of weapons stating he feels this is the best piston operated M16 variant commercially available.  This is a very bold statement of the quality of the LWRC family of weapons.  LWRCI is certainly a company to be taken seriously for potential military contract competition.  The management of LWRCI has clearly demonstrated they are committed to quality, durability and reliability.  Is the piston operated rifle the future?  That is unknown.  Many companies have come out with piston operated rifles due to it being customer driven.  Thus far the U.S. Army has made its position very clear on the issue believing that the existing M4 and its proven direct gas system are working well and are the weapon of choice by our American warfighter.  Nevertheless, there my be an open competition for the U.S. armed forces next battle rifle over the next few years.  There is no question the battle proven M16A4 and M4 carbine will be the baseline and the weapons the competitors will try to beat and those weapons to challenge the mainstay will undoubtedly be piston operated rifles.  You can rest assure piston operated entries will be entered by Heckler & Koch, Colt and FNMI.  But do not be surprised to see a LWRC International entry to compete for the gold.