LWRCI (Land Warfare Resources Corporation International) was created in 2006. Its mission was to produce short-stroke gas-piston ARs to eliminate perceived shortcomings of Stoner’s original direct gas-impingement mechanism. The result was a family of gas-piston rifles and carbines that, the company claims, operate cleaner, quieter and with greater accuracy, reliability and service life. The debate over the relative benefits of DGI vs. piston systems will rage on for as long as ARs exist, but there’s little argument that LWRCI’s piston design is state-of-the-art.
A More Perfect Piston
LWRCI’s self-regulating short-stroke gas-piston system eliminates the venting of carbon-laden gases into the receiver and bolt carrier group, thus moderating the intensive cleaning regime necessary for DGI rifles in heavy use. It also means the bolt-carrier group and associated springs and gas rings are not subject to the searing heat of the tapped gasses—one of the major causes of small parts failure in the original platform. The result is enhanced reliability, regardless of maintenance. Plus, recoil is lighter and muzzle rise is reduced, even though the LWRCI guns are ergonomically identical and weigh almost the same as DGI ARs.
The primary challenge for LWRCI was that previous piston systems utilized a long, thin, one-piece piston rod that was difficult to machine to proper tolerances and then correctly heat-treat so it would not eventually bend and cause a stoppage. The company developed a segmented piston consisting of a piston cup that fits over the gas plug, an operating rod that contacts the bolt carrier and an intermediate rod that connects them. This design permits enough play to reduce the likelihood that the rod will bend or bind. The interface of the piston cup and gas plug also allows the cup to be scraped clean with each stroke, expelling the residue. During endurance tests, this piston system has run without maintenance or cleaning for the entire service life of the rifle with no failures and no carbon buildup.
As the piston assembly drives to the rear in its half-inch stroke, the operating rod strikes a thrust shoulder machined into the bolt carrier. Bolt-on thrust shoulders in some other piston designs have proven prone to failure, so the LWRCI shoulder is machined integral to the carrier. Other piston designs have also suffered from “carrier tilt,” where the off-center thrust of the piston causes the bolt carrier’s body to tilt downward at the rear, which can cause the lower receiver and buffer tube to wear unevenly and eventually lead to failure.
The outside rear diameter of the LWRCI carrier is therefore larger, with machined skids at the bottom to distribute friction more evenly over a wider surface. The bolt carrier’s sides are faceted instead of round to provide firing debris a location to accumulate instead of binding. Plus, the bolt carriers of all LWRCI rifles and the moving parts of the action are all coated in NiBor, a very hard plating process that includes a nickel composite that serves as a permanent lubricant. It minimizes the need for break-in and liquid lubrication, and nearly eliminates corrosion while providing permanent lubrication to the moving parts. The result is an extremely smooth and positive action cycle. On the REPR 7.62/.308 LWRCI rifles, the bolt itself has eight heavy-duty locking lugs, including one on the extractor for a solid match-up with the barrel at the end of the cycle.
Another significant improvement over standard ARs is barrel design. LWRCI rifles and carbines utilize cold hammer-forged 41V45 steel-alloy barrels. Cold hammer-forging takes an oversize barrel blank and, using high-pressure rotary hammers, compacts the barrel blank over a mandrel. This forms rifling devoid of tool marks. It also compacts the molecular structure of the metal, making it denser and stronger. LWRCI treats the entire barrel—inside and out—with NiCorr surface conversion technology, which is a ferritic salt bath that actually hardens the surface of the steel to about .005 inch.
This resists corrosion better than phosphate or oxide finishes. Because it’s not a plating, there’s no concern about flaking or pits that can be a problem with chrome. NiCorr surface conversion is slicker, harder wearing and more heat and corrosion resistant than the hard chrome normally used in service rifle bores. LWRCI barrels test to 20,000 rounds before replacement, as compared with 6,000 to 10,000 rounds for a standard-issue M4.
The new REPR series 7.62/.308 rifles share all these basic LWRCI innovations in a slightly larger platform. Like the 5.56/.223 guns, the REPRs are loosely based on the Stoner architecture of modular upper and lower receiver groups. Most of the ergonomics and handling characteristics of the classic AR platform are the same. Rapidly interchangeable upper receiver groups from the short REPR 12.7-inch through 16- and 18-inch lengths to the 20-inch barrel allow various departments (or individual users) to reconfigure their REPRs for different applications.
The REPR’s nonreciprocating charging handle is mounted on the left side of the upper receiver and has an integrated forward assist. This allows the shooter to operate the action while maintaining cheekweld and keeping his eyes on target. It also allows for greater mechanical leverage during manipulation. Another benefit of the relocation is a tighter fit between the rear ends of the upper and lower receivers, which eliminates gas blowback into the user’s eyes when employing a suppressor or should a cartridge blow.
The gas regulator has four detent positions: Closed (C), Suppressed (S), Normal (N) and Adverse (A). The marking that is at 12 o’clock, nearest the top rail and farthest from the barrel, indicates the setting in use. The shape of the regulator is an irregular ellipse to allow the shooter to determine the active position by touch. A handy gas-knob adjustment wrench is included with each rifle to aid in easy adjustment. Different power levels and bullet weights may require adjustments to the setting for peak performance.
REPR muzzles have a target crown concentric to the bore to further enhance accuracy, and barrels feature match-grade polygonal rifling. All REPRs are available in basic matte-black Type 3 hardcoat anodizing or with olive drab green or flat dark earth Cerakote. This is a type of thermal-cured firearms coating that is applied over the top of the standard finish and offers superb abrasion and corrosion resistance. It incorporates the benefits of Teflon without compromising durability, and its self-lubricating qualities mean the REPR runs with less external lubricants, which people operating in dry and dusty places certainly appreciate.
REPRs are available in a number of configurations. All come with Magpul MIssion ADaptable (MIAD) pistol-grip kits and bolt-on rail adapters for the handguards. All also feature quick-detach handguard tops for easy access to the gas system. The REPR 20 Sniper Model is fitted with a heavy-profile 20-inch barrel, two-stage adjustable match-grade Geissele trigger and Magpul Precision Rifle Stock with adjustable cheekpiece and length of pull. It is intended as a precision rifle suitable for engaging point targets out to 800 meters. The REPR 18 Designated Marksman Model is fitted with a medium-heavy-profile 18-inch barrel, two-stage nonadjustable match-grade Geissele trigger and telescoping Magpul Utility Battle Rifle stock. This model is suitable for point-target engagements out to 700 meters.
The REPR 16 Standard Model has a medium-profile 16-inch barrel, Enhanced Service Fire Control Group (semi or select fire) and telescoping Vltor EMOD buttstock. It is configured as a battle rifle that can engage point targets out to 600 meters. For military and law enforcement use there is also the REPR 12 Standard Model, which is fitted with a medium-profile 12.7-inch barrel, Enhanced Service Fire Control Group and telescoping EMOD buttstock, intended for use up to 300 meters. ALL LWRCI rifles are marked with the “automatic” setting, but it is only functional in military and law enforcement select-fire versions.
Refined and Accurate
I received a REPR 20-inch Sniper Model and 16-inch REPR Standard Model for review, the Sniper in flat dark earth Cerakote and the 16-inch Standard Model in olive drab green. I’ve had a fair amount of field experience with 7.62mm/.308 ARs over the years, and I will say up front that these were the most impressive I’ve ever handled. They are heavy, full-size pieces (the 20-inch weighs 111/4 pounds unloaded without optics), but well balanced and solid as a rock in construction. The standard-issue LWRCI refinements—MIAD grips, “custom” buttstocks, precision triggers, custom-configurable handguards and the side charging handle—made them a joy to operate.
But I’m also an accuracy freak. LWRCI calls these things “Rapid Engagement Precision Rifles,” rated for effective accuracy at extreme ranges. So I equipped the 20-inch Sniper version with a new Trijicon 3-15x44mm TARS Tactical Application Rifle Scope and the 16-inch Standard version with a Trijicon new SRS Sealed Reflex Sight (see accompanying review) and went to work. I selected six varieties of commercial .308 Winchester ammunition in different bullet weights and configurations from 150 grain to 180 grain and fired five five-round groups with each load through each gun at PASA Park’s 100-meter range. The results are on the chart.
The combined overall average for the 20-inch REPR with the Trijicon TARS at 15X magnification was .97 inch (.85 MOA at 100 meters). For the 16-inch Standard REPR with the 1X Trijicon SRS the overall combined average with the same loads was 2.46 inches (2.15 MOA at 100 meters). The difference was due entirely to the difference in magnification of the optics and the fact that the SRS has a 13/4-MOA illuminated dot (not intended as a precision long-range optic). But think about it: Even with zero magnification and a nonprecision reticle, the 16-inch REPR still put everything inside a coffee cup at 100 meters. With a high-magnification scope it would shoot right beside the other gun. The 20-inch Sniper version was a minute-of-angle shooter all the way. I was so impressed, in fact, that I put a 10-round group on paper at 200 meters with the best-performing Black Hills load in the 20-inch rifle just to see. It went 1.88 inches (.82 MOA). And both guns ran all the loads flawlessly with no adjustments needed to the gas-system dial.
Minute-of-angle 7.62mm AR-platform rifles right out of the box. The REPRs are the best-made guns of this type I’ve ever seen. They’re also very expensive, retailing for well over $3,000, but worth every penny. Wish I could afford one.