Not long after Mr. L. James Sullivan designed the .223 caliber Mini-14 for William B. Ruger in 1967, a U.S. Army general officer told Bill Ruger that had the rifle been available a few years earlier, the U.S. Army would have adopted it. It’s true that a decade earlier, General Willard G. Wyman, commander of the Continental Army Command (CONARC), had twisted Eugene Stoner’s arm to design a rifle similar to the U.S. M2 carbine in the new “twenty-two” caliber. Stoner did, but when ArmaLite’s experimental .222 Remington caliber AR-11 blew up, he talked the general into taking a look at his AR-10 in a reduced size. When General Wyman agreed, Stoner had ArmaLite’s L. James Sullivan and Robert Fremont redesign the AR-10 to become the AR-15. Yes, it was the same Jim Sullivan, and the AR-15 was destined to become one of the most prolific rifles in the world.
Never being a fan of what he reportedly referred to as “ASSault” rifles, Bill Ruger hoped that the more traditional Mini-14 would steal some thunder from the AR-15 rifle, and the Ruger certainly established a long, loyal following. However, there’s no doubt that Ruger’s subsequent failure to offer all but 5-shot magazines for the Mini-14 held it back. While all that has changed and the Mini-14 is more popular than ever, the company has also taken a giant step forward with a new rifle. It is Ruger’s own variation of the AR-15.
Called the SR-556 (Sturm, Ruger 5.56x45mm), the rifle looks much like any conventional U.S. M4 carbine clone on its exterior, but it’s a different story on the inside. Starting at the muzzle, the SR-556 has a slotted screw-on flash suppressor similar to that found on the M4 carbine, but with a contour more like that of the flash suppressor once available on the Mini-14GB rifle. Extending back is a standard, plain barrel without the reduction cut used to mount the M240 40mm grenade launcher on M4-type carbines. Next comes the gas block, which certainly gives the SR 556 a unique appearance, and here’s where it starts to get interesting.
In the front of the gas block is an adjustable gas cylinder plug with three positions: one for normal operation, one allowing more gas to enter the system, and one for removal of the plug and piston. The gas block has neither a bayonet lug nor a front sight, the latter being mounted atop the rifle’s quad M1913 rail system with a mate for the front sight mounted on the rear of the gun’s flattop receiver rail.
From here on back, down and around, the SR-556 is identical to any other high-quality semi-automatic M4-style carbine, and it comes with a MilStd recoil spring tube. The pistol grip is by Hogue, and the SR-556 comes with two excellent Magpul 30-round P-MAGs.
Going inside the SR-556 we’ll start back at the gas plug. Using the point of a bullet or similar tool, the gas plug can be turned to four positions, three for as many gas settings with the fourth position allowing the plug to be removed from the front, as already mentioned. The plug’s retaining spring can fall off when the plug is withdrawn, so care must be taken not to lose it. Being somewhat similar in appearance to a pop-top on a soft drink – (OK, beer) can, this spring has a hole that would allow it to be secured somewhere to prevent loss.
With the gas plug and spring removed, the hard-chrome, short-stroke gas piston will normally fall out, hopefully into one’s hand. Yes, Ruger’s new AR-type carbine is piston-operated. However, the piston is the only thing that will come out of the gas block, as the operating rod and spring are permanently housed inside the one-piece quad rail handguard above the barrel. So, how do you get at them to clean or lubricate them? You don’t. Would you ever even have to? I don’t know, but Ruger obviously doesn’t think so. In actuality one could squirt solvent down the captive op-rod to flush it out if need be.
What about disassembling the quad-rail handguard to get at the operating rod and spring? Not gonna’ happen. Not only is the quad-rail one piece with no removable bottom rail, but it is also pinned to the barrel nut at the top and bottom. These are not standard pushpins, but appear to require a special fixture to assemble. This entire, unique rail handguard is made for Ruger by Troy Industries, as are the folding sights, but they bear the Ruger name.
Any piston system in the AR platform requires a special bolt carrier, and that of the SR-556 certainly fills that bill. Instead of a conventional gas key, this carrier has a robust strike plate surface on which the oprod impinges, and this carrier has a counterpart to prevent the carrier from tilting at the rear. Not present in the direct gas system around which the AR-15 was conceived, this dipping of the rear of the bolt carrier has been a bone of contention since conventional piston drives were first introduced to the AR platform decades ago with the RHINO System.
In the RHINO, a cushioning device was used inside the gas key in an effort to prevent tilting. Bolt carrier tilting is simply a matter of physics, where the op-rod strikes a high point in the front of the carrier causing the smaller diameter rear end to tilt down, usually striking the bottom of the bolt channel.
How much of a problem bolt carrier tilt is remains to be seen, but several companies have sought to avoid it by adding material to the bottom/rear of the carrier. In Ruger’s case, the diameter of the entire carrier is larger for about 0.7 inch. For some reason, at least on my sample, the standard rails on the bottom and top of the carrier are truncated. The carrier and bolt are hard-chrome plated to wear literally forever, with this tough finish also providing lubricity The Ruger’s chamber and bore are also hard-chrome plated.
The SR-556’s lower receiver bears the Ruger logo, model designation and serial number on the left side and the exterior is finished in the usual MilSpec hard anodize and phosphate. The SR-556 comes in a padded, zippered black case bearing a large red Ruger falcon logo, and the aforementioned two Magpul 30-round P-MAGs, a cleaning kit and a lock. It also comes with three rail covers to protect both the hands and rails from damage.
While Sturm, Ruger’s new 9x19mm NATO autopistol, the SR9, was introduced prior to the SR-556 rifle, it is a fitting companion piece to the rifle. Similar to other pistols using a partially retained striker system of operation, the SR9 makes the same claim of being a double-action gun.
However, unlike some pistols of this ilk, the SR9 not only points naturally in the hand but also comes with a positive thumb safety. Subtle in comparison to some others, this thumb safety can be deployed all the time or when desired. After watching one of my best friends bleed to death in an alley as a result of “gun-grab,” I’m a manual safety advocate, and I use them.
Should this thumb safety be larger? The jury is still out. Some would want it larger to permit using the “high thumb” position with the thumb ON the safety, while others would prefer to “wipe” the safety down to the OFF position, allowing the thumb to then pass by it and grip lower. Seeing more advantage to “high thumb,” I would like to try an aftermarket large thumb safety on the SR9, and I believe it would be an improvement.
Made of stainless steel, the SR9’s slide can be had in a natural or matte blue finish; while black is the standard color of the pistol’s polymer frame, it can also be had in OD green. Of course, this component has its own integral frame rail on the dust cover portion to mount the light or laser sight of your choice. I tested the SureFire X300 with it and it fit the rail perfectly. The magazine holds 17 rounds of 9x19mm NATO ammunition plus one in the chamber. This is three times the amount of ammunition contained in the 6-shot revolver I carried for the first 18 years of my career. With the great advancements made in contemporary 9mm ammunition, this gives the user an advantage in a gunfight.
Law Enforcement Application
Although both the SR-556 and SR9 are available to law-abiding Americans, both also have great appeal to the law enforcement officer. It was found that most holsters designed for the Glock pistol will also accept the SR9 pistol and one in particular was right at home with the new Ruger. This was the BlackHawk SERPA, whether the standard or tactical model. In the latter, the pistol locked in perfectly and yet was instantly accessible by the operator.
As for lights, any of those from Insight Tech-Gear or Sure-Fire worked fine on the rail and could be stored on the side panel of the Tactical SERPA holster along with a spare magazine. For the person who isn’t a “gunny,” the SR9 is uncomplicated and the recoil of the 9x19mm cartridge is easy to control.
Like other members of the AR-15 family, the SR-556 lends itself to a number of aftermarket custom features. Although the rifle comes with rail forend and flip-up iron sights, it does not come with a front sling mount and it is equipped with the standard adjustable buttstock. Thus I equipped the rifle with my favorite forward sling mount, the ACE Sling Mount, from DoubleStar. I also slipped off the buttstock and replaced it with a Vltor E-MOD Stock in black to match the rest of the rifle. Housing two long spare-battery tubes and a spare parts compartment, this stock also has a great nonslip rubber butt and an equally good QD side sling mount.
By the way, if you prefer different colored accessories to avoid excessive heat or to make your SR-556 two-tone, the Vltor E-MOD Stock can also be had in OD green and flat dark earth. Both the ERGO Grip from Falcon Industries and the TangoDown Pistol Grip, as well as the Magpul Pistol Grip can also be had in these colors. Standard and slim rail covers from all three companies can also be had in the same colors, as can Magpul’s P-MAG.
Another accessory that can be had in the big-three colors is the sling, such as those offered by Wilderness Tactical, Blue Force Gear and others. In fact, the industry offers as many different slings as AR-15 clones. For the SR-556, I selected a black Vickers Sling from Blue Force Gear. With an instant let-out system allowing one to transition or get out of the sling quickly, the sling can just as quickly be taken back in for standard deployment and carry. If you prefer a single-point sling, both of the above companies offer this and other varieties.
Another fabulous piece of gear I happened to receive for eval was the brand new Mk I.c Duty Jacket from Kitanica. Having previously checked out this company’s Mk IV jacket, I was familiar with the high quality and unique features Kitanica puts into its well-designed high-performance jackets, but the Mk I.c surprised me. With multiple pockets able to house a second, or primary handgun (including the SR9), this jacket is loaded with other features including a shoulder flashlight mount, drag strap, cell phone pocket, Velcro insignia panel and many more.
Although Kitanica didn’t intend it, I found that the Mk 1.c can even carry a badge. Made of super tough Cordura Nylon, Kitanica action jackets hold out moisture while holding in body heat. I’ve worn them outdoors in comfort in the dead of winter over just a light shirt.
Oh, yes, and it’s made in the U.S.A.
For all round deployment of the SR-556, I mounted a GripPod on the rifle’s bottom rail. The most widely adopted weapon stabilization system in the history of the U.S. military, the GripPod is standard issue with the U.S. Army and all Reserve and National Guard components, the U.S. Marine Corps, many units of the U.S. Navy and Air Force, Delta Force, and federal civilian law enforcement agencies. Even Great Britain now issues the GripPod to the entire British Army. The GripPod is available from U.S. Tactical Supply, Brigade Quartermaster, LA Police Gear, Mounting Solutions Plus, RSR, Brownells and others.
Made of the finest materials, the standard GripPod will support a 250-pound man while the SAW version will support 400 pounds. Even the new, less expensive LE GripPod will support a 180-pound man standing on the rifle with the Grip-Pod deployed. Available in black or tan, the GripPod now can be had with a matching dual M1913 rail in these colors. Allowing a weapon light to be activated by the support thumb, this rail does away with wires, Velcro, remote pressure switches and ACCIDENTAL LIGHT, which can result in bullets coming your way. I mounted a SureFire G2 LED Tactical Light with an optional protective end cap on my GripPod using a Vltor 1” ring mount and had the best of all worlds at my fingertips. No rail system? No problem. Companies such as Mounting Solutions Plus carry short M1913 rail panels that can be mounted on the bottom handguard in order to mount a GripPod or other vertical grip.
The entire above setup weighs about 12 oz. and would cost about $200 to put together on a LE Grip-Pod. Using this bipod system, one can go from standing or walking to prone and putting rounds on target at 200 yards and beyond in half the time or better. When seconds count…Well, you do the math, but that’s why the GripPod is part of the U.S. Army’s M4 kit. Rumor has it that a major light/laser company is now designing a new system around the GripPod with IR capability to boot. Stay tuned.
Armadynamics Ambi Charging Handle
Another worthwhile accessory I added was the new Armadynamics Ambidextrous Charging Handle from Mounting Solutions Plus. Designed at the request of a component of the U.S. Army, this charging handle can be used from either side to cock the M-16 or any of its variants and is ideal for both left- and right-handed operators.
Shooting the Sturm, Ruger SR9 pistol brought no major surprises. The pistol’s trigger is not match grade, but “duty-safe” in my opinion, with a crisp letoff. Accuracy was very good with 3-inch 5-shot groups being achieved at 25 yards, and recoil was very controllable. In short, it should make a lot of training officers happy. The magazine is easy to load until the last few rounds and, as mentioned, the pistol comes up on target naturally for 99.9 percent of users. There if you care to use it (I DO), the thumb safety is out of the way, but can be taken off instantly when desired, making the pistol ready to protect oneself or the lives of others.
The SR-556 also brought no surprises. Although questions were raised about additional felt recoil from its piston operation, if there is any, I’m simply not conscious of it. Then again, I’m used to .308, .300 Mag, .45–70 and 12 ga. shoulder arms, so when others discuss “excessive” recoil from a .223, I’m no expert. The SR-556 did not recoil any more than an M4 carbine I fired side by side with it. In fact, possibly due to its slight extra weight, the SR-556 seemed to recoil less.
The SR-556 performed as expected; same trigger pull, same controls, MOA accuracy and no malfunctions to date, just like any other AR-platform rifle. Optics used in eval included the Aimpoint Comp M4 Red Dot and the Leupold 3–9X 30mm MR/T Scope in A.R.M.S. #17 ThrowLever 30mm rings. The Leupold 1–4X MR/T is also an excellent choice for urban use by a law enforcement first responder, and allowed me to achieve 5-shot groups ranging from 1.5 to 2.5 inches at 100 yards, which is not bad considering the standard GI trigger. A match-type trigger would no doubt improve accuracy, but the issue trigger will. I also tested a brand new 40-shot magazine now being evaluated by an element of the U.S. military.
While this magazine is not yet available, it, the Magpul P-MAG and standard GI-issue 30-round magazines all worked perfectly in the SR-556 with no malfunctions occurring. If you’re looking at the AR platform, or an affordable autopistol, check out what’s available from Sturm, Ruger & Co., 1 Lacey Place, Dept. SOF, Southport, CT 06890, (203) 259-7843 (ruger.com). To keep your Ruger and the rest of your guns, JOIN THE NRA…DO IT
230 West Center St., Dept. SOF
West Bridgewater, MA 02379
14103 Mariah Ct., Dept. SOF
Chantilly, VA 20151
BlackHawk Products Group
6160 Commander Way, Dept. SOF
Norfolk, VA 23502
Blue Force Gear
PO Box 853, Dept. SOF
Pooler, GA 31322
Brigade Quartermasters Ltd.
1025 Cobb Intl. Hwy., Dept. SOF
Kennesaw, GA 30152
200 S. Front St., Dept. SOF
Montezuma, IA 50271
PO Box 430, Dept. SOF
Winchester, KY 40391
23 Industrial Dr., Dept. SOF
Londonderry NH 03053
PO Box 1690, Dept. SOF
Edgewood, NM 87015
LA Police Gear
28022 Industry Dr., Dept. SOF
Valencia, CA 91355
PO Box 99095, Dept. SOF
Emeryville, CA 94662
Leupold & Stevens, Inc.
PO Box 688, Dept. SOF
Beaverton, OR 97006
PO Box 17697
Boulder, CO 80308
Mounting Solutions Plus
10655 SW 185 Terrace, Dept. SOF
Miami, FL 33157
RSR Group, Inc.
4405 Metric Dr., Dept. SOF
Winter Park FL 32792
Sturm, Ruger & Co., Inc.
411 Sunapee Street
Newport, NH 03773
18300 Mt. Baldy Cir., Dept. SOF
Fountain Valley, CA 92708
4720 N. La Cholla Blvd.,
Tucson, AZ 85705
US Tactical Supply, Inc.
939 Pacific Blvd., S.E., Dept. SOF
Albany, OR 97321
Vltor Weapon Systems
3735 N. Romero Rd., Dept. SOF
Tucson, AZ 85708
Wilderness Tactical Products
1608 W. Hatcher Rd., Dept. SOF
Phoenix, AZ 85021
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