Review: Ruger AR-556
May 09, 2016
I'm a man who can admit when I am wrong — no matter what my ex-wife might say. When I heard Ruger was introducing a direct-impingement AR-15, I mentioned to a colleague it would likely be both a little too heavy and a little too expensive for what the current market can bear, as I feel is the case with the company's gas-piston AR-15 line. News flash: I was completely wrong. With the Ruger AR-556, the company has created an AR-15 shooters want.
Currently, the most popular AR-15 configuration is a 16-inch flattop model with a carbine-length gas system and collapsible stock, commonly known as the M4 style, as it most closely resembles our military's M4 carbine. That might not be the kind of whiz-bang AR-15 you see on all the magazine covers, but it's the best selling of any AR-15 type across the country. And Ruger, as much as any gun company, knows its customers.
Considering how flat gun sales have been for the past year, introducing the new Ruger AR-556 at a suggested retail of only $799 is nothing but smart. Ruger is able to do this because it is a big company and makes everything on the rifle in-house, including some new parts you might be surprised to see. And here's something else. This is the first firearm from Ruger designed, engineered and built completely in its new Mayodan, N.C., facility.
Ruger AR-556 Features
The Ruger AR-556 features a 16.1-inch, cold hammer-forged barrel of 4140 chrome-moly steel. Ruger says the AR-556 has a medium contour, but to my eye it appears to be a hair thinner than most of the medium-weight barrels on the market. I think that's a good thing.
Under the handguard the barrel has a gentle taper, and as a result, total weight of the Ruger AR-556 is 6.5 pounds, which is exactly what it should be on a general purpose AR-15. If you're looking for specifics, under the handguard the barrel is .850 inch, under the gas block it is .750 inch and forward of the gas block to the flash hider it is .700 inch.
The six-groove barrel features a 1:8 twist. This twist has been found to be the best for the widest range of bullet weights (from 35 to 77 grains). The Ruger AR-556 has a 5.56 NATO chamber, so it will handle the more common .223 Rem. ammo as well as the slightly hotter 5.56 NATO round (which will be most of the surplus military ammunition). The barrel has M4 feed ramps for improved reliability.
The flash hider on the end of the Ruger AR-556 barrel has the distinctive Ruger look. It has five slots and is just a hair shorter than the standard military A2 flash hider. Unlike the A2 hider, it does not have a closed bottom, so if you do any shooting from the prone in a dusty area you might find yourself kicking up a cloud. The muzzle has standard 1/2x28 threads, so it will accept any standard AR muzzle device.
The metal parts on the Ruger AR-556 display an even satin black finish. Officially, the finish is matte black oxide on the barrel and hard-coat anodizing on the receivers, but it all matches and looks good. You'll see the Ruger logo discreetly everywhere — on the lower receiver, upper receiver, stock, pistol grip, rear sight and handguard.
The front sight/gas block on the Ruger AR-556 might look a little different to AR-15 fans. It is not a mil-spec forging but rather a refined design that's machined in-house at Ruger. It is F height, so it will co-witness with optics. The front of the sight tower is serrated. The people at Ruger say this is to reduce glare, but I can't say I've ever had a problem with glare off the front sight post of an AR. It looks cool, though, and further helps to set the Ruger apart in a crowded market.
The front sight tower/gas block also features a bayonet lug on the bottom, as well as a QD sling socket, which I thought was a very smart feature. The front sight is adjustable for elevation, and a tool to do that is included with the Ruger AR-556.
Paired with the fixed front sight is a pop-up polymer rear sight I first thought was a Magpul. But remember Ruger makes the entire gun in-house. In fact, the rear sight is Ruger's Rapid Deploy rear sight. It pops up by depressing a serrated button on the left side of the sight body. The sight features a single aperture that is click adjustable for windage by a knob on the right side of the tower.
The front and rear Rapid Deploy sights seem to be just as well-made and designed as the popular Magpul MBUS sights and are available for sale on the Ruger website. As of right now, the new pistol grip is not available for sale separately, but several of the employees I talked to at Ruger are in favor of that.
Ruger supplies one Magpul PMag with the Ruger AR-556. While the military is still issuing aluminum magazines, in truth the Magpul PMag is the AR magazine standard against which all others are currently judged and has proven itself in combat around the world. The polymer buttstock is an M4-style manufactured by Ruger, and it rides on a six-position mil-spec buffer tube.
The round handguard on the Ruger AR-556 is the narrower, original design seen on CAR-15s. Current military M4s sport fatter handguards because they have a double aluminum heat shield inside to protect the user's hands during full-auto fire. The Ruger handguard is constructed of heat-resistant glass-filled nylon. It fits into a standard round metal handguard cap at the front, but if you look closely, you'll see the barrel nut and delta ring are a new style from Ruger.
Apparently as fed up as the rest of America at how difficult is it to remove a handguard, the engineers at Ruger designed their own delta ring and barrel nut. There is a patent pending on their new barrel nut, and to remove the handguard all you need to do is unscrew the polymer delta ring toward the receiver. When it stops moving, the rear of the handguard is clear of the ring, and the upper and lower halves will pop right out.
Compare that to the standard spring-loaded delta ring. If you want to swap out handguards with one of those, you'll need tools or three hands and a monkey. All standard two-piece carbine-length handguards will fit on the Ruger AR-556, too. Why somebody didn't design a rational delta ring like this 40 years ago I have no idea, but it is simply genius.
The pistol grip on the Ruger AR-556 is obviously not a military-style A2, and at first glance I thought it might be an aftermarket item, but it is in fact one of Ruger's own design. It has a beavertail for optimal trigger reach and a slight palm swell.
The pistol grip is paired with an oversize polymer trigger guard. This type of trigger guard is useful if you're wearing gloves, and most people think they look better than the standard straight trigger guards. There is no gap between the pistol grip and trigger guard to pinch your middle finger.
Fit between the upper and lower receivers was tight, and I had to use a punch to move the rear takedown pin the first time I took the rifle apart. Receivers are made from 7075-T6 aluminum forgings. The bolt and carrier came from the factory well-lubed with light oil.
I would have been happy if the Ruger engineers had worked the same kind of magic with the trigger group as they did with the delta ring. Trigger parts are standard GI in design and finish, which means the Ruger AR-556 sports a typical GI single-stage trigger: heavy and gritty. Trigger pull on my sample was 7.75 pounds, and I have no doubt accuracy suffered as I struggled to hold the rifle still while pulling the trigger. But trigger pull was the only complaint I had with the Ruger AR-556. I'm guessing that with a crisp match trigger my group sizes might have been reduced by a third.
Ruger machines its own bolt carriers and bolts. The inside of the carrier is chrome plated, as is the inside of the gas key, which is properly staked. For those of you who worship at the altar of mil-spec, the bolt is made of 9310 steel, shot peened and pressure tested. In fact, Ruger proof tests the bolt and barrel together.
Gas-piston AR-15s stay cooler and cleaner at the chamber, and that was Ruger's big selling point with the SR-556. I prefer Eugene Stoner's original direct-impingement design. If your gun is properly made and lubed, it should run just fine right out of the box for many hundreds if not thousands of rounds between cleanings. To me, the added weight and expense of a piston AR-15 do not make up for the reduced fouling, and by moving to a direct-impingement gun Ruger is able to sell the Ruger AR-556 for substantially less than its SR-556. The longer aluminum railed handguards on the SR-556 add cost and weight as well, and most AR buyers don't need or use them.
If you read gun magazines you'll have seen all the experts drooling over AR-15s with mid-length gas systems, which are two inches longer from receiver to gas port than carbine-length systems. Mid-length gas systems shoot a little softer and have a longer inherent life due to less wear on the moving parts.
So why would Ruger — which has a reputation as being expert at finding out what its customers want — make an AR-15 with a carbine-length gas system when "everybody" knows the mid-length gas system is better? Well, while gun writers and competition shooters have been extolling the virtues of the mid-length gas system for several years, the vast majority of the AR-buying public has never heard of it. And the fact is that the carbine-length gas system in ARs works just fine — as it has for decades.
Ruger AR-556 at the Range
The Ruger AR-556 ran without a hitch. While the trigger was a hindrance to accuracy testing, it didn't slow me down too much when I was just having fun, hammering silhouettes at conversational distances. The rifle comes with a flattop, and as I consider iron sights backups to an optic, I mounted a Trijicon SRS red dot on the Ruger AR-556 when it came time to have some fun. (Ironically, the Trijicon costs more than the rifle.)
When it comes to controllability and shootability and fun (especially for young or new shooters), I'm not sure there's another design on the market that can beat a 16-inch AR-15, unless you're talking a .22 rimfire. The first time I took my girlfriend shooting, I put her behind an AR-15, and my son can shoot one all day long without it hurting his shoulder.
Considering we're talking about a rifle design that when loaded with suitable ammo is viable for self-defense, competition, target shooting and hunting animals up to the size of whitetail deer (where legal), the AR-15 truly is America's rifle.
And despite the attempts of some to demonize it as some kind of "fringe" rifle, our own Dave Fortier lives smack dab in the middle of Kansas farm country and reports that the most common "farm" rifle he sees bouncing around in pickup trucks today isn't the traditional lever-action .30-30 but rather an M4-style AR-15.
With the Ruger AR-556, the company has given America exactly what it wants: a solid U.S.-made basic AR-15 with everything you need and nothing you don't at an affordable price — with a few unique features that show it is unmistakably a Ruger.