CMMG RKM15 Handguard: Heavy firearms are a burden to drag around to a deer stand, shooting bench or 3-Gun match. The .308 AR is already a fairly heavy gun, especially when compared to an AR-15. Add a quad-rail handguard, a bipod and other accessories and you’ll quickly find yourself with a 13-pound carbine. Thankfully, the days of quad-rail handguards are a distant memory with modern manufacturers. Today, any company worth their salt builds KeyMod or M-LOK handguards from aircraft-grade aluminum, providing modularity without being too bulky. CMMG makes a handguard that I really like: the RKM15. As its name suggests, the railed handguard is in KeyMod format, and it’s 15 inches in length. It’s built from 6061-T6 aircraft-grade aluminum and weighs in at a scant 13 ounces. (The barrel nut is another 3 ounces, but this is located so close to the receiver that your rifle’s balance won’t be affected.) KeyMod slots are located in the 3, 6 and 9 o’clock positions while a top Picatinny rail runs the length of the handguard. The RKM15 floats freely and uses a proprietary barrel nut that comes with the rail kit.
ELCAN SpecterDR: You can’t hope to hit what you can’t see, and since versatility is the theme here, I chose the single most versatile optic I have at my disposal—the ELCAN SpecterDR 1.5X/6X scope. Now this isn’t a scope with a 1.5X to 6X magnification range. It can be switched from 1.5X to 6X or vice versa. This is because the ELCAN SpecterDR utilizes an internal glass prism that toggles from 1.5X to 6X magnification with the throw of a small lever. This is the only internal control on the ELCAN, as both the windage and elevation adjustments are external. This was done to ensure that the scope could survive the worst conditions and the most recoil. Additionally, the reticle is illuminated and features multiple settings that change both brightness and what portions of the reticle light up. This goes a long way toward making the optic ultra-versatile because it can act as a short-range reflex sight on the low magnification setting and as a mid- to long-range scope on higher magnification. The latter is easier than it sounds because the BDC reticle is designed for use with .308 Winchester/7.62mm NATO rounds.
Geissele SSA Trigger: The most precise rifle in the world will be incredibly difficult to shoot if it has a spongy 12-pound trigger. If I were recommending a trigger for precision work only, it would be a match trigger with a slightly heavy take-up and a super-light breaking point. But this guide is for making your .308 AR as versatile as possible, and an ultra-light trigger can be a liability when running and gunning in a 3-Gun match, or when sitting in a tree stand fighting buck fever. A better all-around trigger is the Super Semi-Automatic (SSA) two-stage trigger from Geissele Automatics. It combines the two-stage dynamics precision shooters love with just enough weight for snap shooting and CQB work. While the price of the trigger ($240) might scare some people off, the second they try one, they’ll be sold on it.
Harris HBRS: Even after three decades, the Harris bipod remains a staple of precision shooting when a shooter needs added stability with as little added weight as possible. One effective model in particular is ideal for DMR-type rifles—the HBRS. This version of the Harris bipod features two adjustable, spring-loaded legs that extend from 6 to 9 inches when fully deployed. The feet are built from a tough rubber whose friction resists movement on both slick and rough surfaces. The “S” portion of the name designates that the bipod can swivel, allowing for slight lateral movement to adjust for uneven terrain. While there are more stable bipods on the market today, few can come close to the HBRS’ feathery 13-ounce weight.
Hexmag ATG: Built from high-impact polymer and adorned with Hexmag’s hexagonal pattern, the ATG takes a very different approach to grip construction than its competitors. Most AR pistol grips consist of a grip and a securing screw. The ATG is a three-piece system with interlocking teeth in between the grip modules that are secured by a screw. The shooter can adjust the grip’s angle by loosening the grip screw and rotating the pistol grip to one of three positions: 17, 25 or 33 degrees. The first position is the most vertical, and it’s ideal for PDWs, while the second is the standard mil-spec grip angle. The third, however, is what we’re interested in. At 33 degrees, the grip is swept back almost like an old German StG 44 assault rifle, and this is great for shooting from either a benchrest or prone position. Finally, while the grip itself is relatively smooth-textured, the hexagonal indents are designed to accommodate Hexmag’s hexagonal grip tape so shooters can apply grippy surfaces wherever they would prefer
Innovative Arms Deception 7.62: When it comes to sound suppressors, I tend to go overboard. I would rather have one rated for hard use than simply just enough for my intentions. Thus, it was only natural that I was attracted to the budget-friendly, full-auto-rated Innovative Arms Deception 7.62. Made from stainless steel, the Deception is anything but light at 21 ounces. Still, its short 7.6-inch overall length keeps the weight close to the shooter, helping negate some of the heft. With a 33-decibel sound reduction, the Deception makes hunting in the woods with your .308 (where legal) much easier on your hearing. Plus, for guys like myself who have rifles like the CMMG Mk47 Mutant in 7.62x39mm, the Deception’s 5/8×24 thread pitch makes swapping between rifles a breeze.
Lancer Systems L7 AWM: Lancer’s Advanced Warfighter Magazines (AWMs) are second to none in terms of quality and durability. With each AWM, Lancer takes an ultra-tough translucent (or opaque) polymer body and molds it around a steel reinforcement collar. The steel collar doesn’t just protect against accidental damage to the magazine. It’s also designed to ensure that continual wear on the magazine catch doesn’t alter the feeding angle and negatively affect reliability. Lancer’s latest addition is the L7 AWM. Available in five-, 10-, 20- and 25-round varieties, these new magazines are as tough as nails. For our rifle, the 25-round version is a little too long if the shooter wants to fire from the prone position. The 20-round L7 AWM, however, offers the perfect balance of capacity and compactness in a mag.
Magpul ACS-L: As a general rule, anything shorter than a 16-inch barrel/carbine-length gas system combo will require tuning to function with standard-pressure ammo. The recoil impulse from a .308 out of a short barrel is just too violent for the buffer assembly to keep up with. Symptoms of this normally include ejected casings turned 180 degrees inside the chamber, or simply a stuck chamber because the bolt traveled too quickly to throw the shell out the ejection port. Because of this, I’ve gone with the minimal barrel length possible that doesn’t require a tax stamp by venturing into NFA territory: 16 inches. This barrel is paired with a carbine-length gas system and carbine buffer assembly, which has the added benefit of accommodating a collapsible stock. My favorite stock to use on these rifles is the Magpul ACS-L carbine stock. The ACS-L provides the perfect comb height for optics and overall length suitable for smaller-statured shooters and NBA centers alike. Plus, it features a texturized rubber buttpad that helps reduce felt recoil while enhancing control by resisting movement on the shooter’s shoulder.
Magpul Enhanced AR Mag Release: This one is pretty simple. It’s a drop-in replacement for an AR magazine release button. While it’s not really necessary for regular use on standard AR-15 carbines, the elongated .308 receiver makes reaching the standard release difficult for most. Installation is simple; a shooter just removes the old release, pops in the Magpul button and then secures the extension with two Allen screws. The entire kit is made from aircraft-grade aluminum that has a dull hardcoat anodized finish to protect against corrosion and undue wear.
Next Level Armament NLX 308: Despite being longer than a standard AR-15 charging handle, the .308’s latch is the same size. This is unfortunate, because the effort needed to rack the action or clear a malfunction is much greater on a .308 than a 5.56mm. This is why I always go for extended charging handles to give my hand more purchase to charge the action. One of the most generously sized latches on the market is the Next Level Armament NLX 308. This fully ambidextrous charging handle resembles a battle axe, and it’s nearly bomb-proof in its construction. The handles themselves are heavily textured to prevent a shooter’s hands from slipping when wet or oily. In terms of pure ergonomics, this upgrade goes the furthest in improving the handling of any stock .308 AR.
The AR-15 is arguably the most prolific centerfire carbine in America. Available in dozens of calibers and millions of configurations, the rifle can be easily tailored to meet every shooter’s needs and desires. Unfortunately, the same can’t be said of its larger .308 Winchester/7.62mm NATO brethren.
- RELATED STORY: 39 New Rifles & Carbines You Should Focus on in 2017
There are sometimes magazine compatibility issues among big-bore ARs. But for the purposes of this article, I’ll be dealing with the most popular .308 AR platform: SR-25-pattern rifles. These are functionally identical in operation to their 5.56mm NATO counterparts, but with certain components scaled up accordingly to handle the larger rounds.
And while there aren’t as many aftermarket options for .308 AR rifles, that doesn’t mean there isn’t a slew of awesome accessories on the market for your big-bore blaster. With this concept in mind, here are the top 10 accessories to transform your .308 AR into a versatile fighting rifle.
- RELATED STORY: Feeding Frenzy – Charting the History of AR Magazines
For more information about these .308 AR upgrades, visit the following sites.
CMMG RKM15 Handguard
Geissele SSA Trigger
Innovative Arms Deception 7.62
Lancer Systems L7 AWM
Magpul Enhanced AR Mag Release
Next Level Armament NLX 308
This article was originally published in “Tactical Weapons” August/September 2017. To order and subscribe, visit outdoorgroupstore.com.
Two suppressor-capable big bores, the Sig Sauer P227 TACOPS and the FNX-45 Tactical, slug...
by Garrett Lucas / Sep 8, 2017