The LWRC M6-SL is a piston AR and LWRC's effort to build a lighter rifle. It features a heavier H2 buffer that reduces recoil so you get back on target quicker.
December 15, 2011
By James Tarr
Over the last few years, LWRC (Land Warfare Research Center) International has successfully established itself in the crowded AR market. It has done this by producing rifles and carbines that are well above the norm not just in quality but in performance. The only knock against LWRC guns is that they are both heavy and expensive. The new M6-SL (Stretch Lightweight) has been designed specifically to address both these factors.
LWRC's M6 is a proven self-regulating short-stroke gas piston AR rifle, and the M6-SL Stretch Lightweight is designed to replace the base model M6. Called the Stretch because it uses a mid-length piston system, LWRC has proven that it is actually possible to make a piston-driven AR as light as a gas gun. The M6-SL weighs just 6.44 pounds empty, which is substantially lighter than most of the company's offerings. In fact, the M6-SL is the lightest piston-driven AR I'm aware of.
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To help keep the weight down, the rifle is equipped with a 16.1-inch light-contour barrel. Many custom AR manufacturers seem wedded to the idea of heavy barrels to "ensure the utmost in accuracy during long strings of fire," but when it comes to carbines meant for personal defense or for law enforcement, you're simply going to run out of ammunition before you can get even a thin AR barrel hot enough to get its zero wandering. And even then, any well-made AR will still be more than accurate enough to hit human-size targets at any distance you're likely to be engaging them in self-defense.
The M6-SL comes with Magpul MOE furniture, which is not just better designed than the mil-spec components it replaces but tougher, without adding unwanted weight. The mid-length MOE fore-end may not be as sexy-looking as the quad rail fore-ends everybody seems to be throwing on their rifles, but quad rails add weight on the front half of the gun, where you'll notice it the most. Unless you're active duty military you won't need to clamp anything other than perhaps a flashlight onto the end of your rifle, so unless you can't live without the "cool factor" of quad rails, why add all that unnecessary weight?
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The M6-SL comes with an enhanced Advanced Combat Bolt, which has been redesigned to improve reliability, especially extraction. The bolt, carrier, and trigger group of the M6-SL are coated with the EXO (nickel-boron) finish from FailZero. EXO is the latest wonder coating in the firearms world and works even better than you might hope. I fired close to 200 rounds through the well-lubed SL during testing, and prior to photographing the bolt and carrier all I did to clean them was wipe them with a dry paper towel. The M6-SL is provided with a small bottle of Slip2000's EWL (Extreme Weapons Lube), which works as well or better than any other AR lube on the market.
The front of the M6-SL's bolt carrier is stamped H2, which means it is to be used with the provided H2 recoil buffer. Heavy buffers (marked at the front with an H, H2 or H3) are designed to slow the carrier during recoil. Combined with the mid-length gas piston system, this heavier buffer helps to tame the recoil of the lightweight M6-SL. Granted, the .223/5.56 cartridge doesn't generate a lot of recoil to begin with, but the heavier H2 buffer can get you back on target a fraction of a second quicker.
The M6-SL comes with a fixed front sight and a Daniel Defense A1.5 rear sight clamped onto the rail. There is still plenty of real estate left on the rail if you want to attach a red dot. The rifle comes with a 30-round Magpul PMAG, the polymer AR magazine against which all others are judged.
The SL's trigger group is standard mil-spec design, but it's coated with EXO. AR triggers as designed are heavy and gritty, but the EXO coating made the SL's both slightly lighter (at 5.5 pounds) and smoother. The rifle averaged better than 1.5-inch groups during accuracy testing off sandbags, but I honestly think with a match trigger it would be capable of even tighter groups.
LWRCI doesn't seem to know how to do anything halfway, and even though the M6-SL is its "base" model, it has as many features and aftermarket accessories as some custom guns, all for a very competitive price.
Fast Specs
Type: piston-driven AR
Caliber: 5.56 NATO
Barrel: 16.1 in., light contour; 1: 7 twist; cold hammer-forged; /A2 flash hider
Overall Length: 33.7-36.7 in.
Weight: 6.44 lb.
Furniture: Magpul MOE
Trigger: 5.5 lb. (as tested)
Sights: fixed A2 front, Daniel Defense A1.5 rear
Price: $1,675
Manufacturer: LWRC International Accuracy Results
Smallest avg. group: Federal 69-gr. BTHP — 0.85 in.
Largest avg. group: Hornady 55 gr. V-Max — 1.64 in.
Avg. of all ammo tested (5 types) — 1.41
Accuracy results are the averages of three three-shot groups at 100 yards from a sandbag rest. Abbreviation: BTHP, boattail hollowpoint