Armalite AR-31 Rifle—New Gun Review

AR-31 Profile Right Side

By Ian Kenney
https://www.armalite.com/

The AR-31 is the latest bolt action rifle from Armalite that has been developed as a short action version of their successful AR-30 and AR-50 rifles. Unlike the AR-30 series of rifles that were chambered in .338 Lapua and .300 Winchester Magnum, the AR-31 is chambered in .308 Winchester, although more calibers may become available in the future. When I first saw the AR-31 with its black barreled action rails, and chassis, the first thing that popped into my mind is “man is that thing tactical”. The AR-31 is more than just a “tacticool” rifle though, as it’s laden with features that make it a heavy-duty precision rifle suitable for Regular Joe’s and Law Enforcement professionals alike.

Here you can see that the ten-round magazine protrudes from the bottom of the rifle very little and the magazine release is easily accessible from the trigger. The magazine fits very well into the well with very little slop or rattle that is a common complaint with some other detachable magazine systems.

Overview

The first thing that a person is going to notice about this rifle when they pick it up is that it is built like a tank and weighs about as much as one too. The rifle weighs just over 14 pounds unloaded and without any additional optics or accessories attached to the rifle. I felt the heft was evidence of its over-engineered nature that makes it able to handle harsh environments and rough use. The octagonal action is beefy and well made, without an excessively large ejection port to keep the action stiff and help with accuracy. Screwed to the front of the action is a 24” long match grade barrel with a 1:10 twist and a factory threaded 5/8-24 muzzle. Even though the rifle comes with a muzzle brake, the end user can easily swap it out for a sound suppressor or any standard .30 caliber muzzle device. The muzzle diameter is .750”, making the barrel contour just a little lighter than Remington’s Varmint contour barrel. The size of the action also allows it to function perfectly with Armalite’s AR-10B magazines, the same magazines used with some of their AR-10 rifles. These magazines are double stack, double feed magazines so a relatively large amount of ammunition can be stored in a lower profile magazine that doesn’t protrude out like other magazines.  The AR-31’s bolt utilizes a floating bolt head design, similar to those in Savage actions, to ensure the lugs always maintain even contact with the action, further helping with accuracy.

The AR-31’s beefy action sports an 18” long 20 MOA rail that ensures you’ll have the elevation needed to get out to longer ranges. Like many purpose built custom actions the ejection port is just the right size to easily eject cases but not so large that it compromises rigidity. Also visible is the paddle safety at the rear of the bolt, while functional it proved to be a little awkward to actuate.

One included accessory that is an additional cost on most other factory precision rifles is an extended 20 MOA base with side accessory rails to mount things like electro-optical devices and IR lasers. The base’s 20 MOA taper is compatible with most quality long-range scopes to ensure that there’s plenty of elevation to reach targets 1000 yards away. The rail is securely attached to the action with four oversized screws, and a lug in the bottom of the base fits into a corresponding recess in the action. There is probably very little that will make the rail budge or flex to the point it would cause an accuracy issue for the shooter.

Here you can see a detailed shot of the Armalite Target Stock with adjustments for cheek height, length of pull, and adjustments to raise and lower the recoil pad. The thumbwheels have a ball detent that keep the adjustments in place while shooting and also provide a tactile reference when turning the knobs. The cheek piece is made from metal but has a rubber pad adhered to it that provides adequate padding and a nice non-slip surface. Also notice the cut outs in the right side of the cheek piece, that is to allow the bolt to be removed only when the safety is on. In addition to those features the stock has pre-threaded attachment points for sling swivel studs and a Picatinny rail bottom to attach other sling swivels or a monopod.

The AR-31 chassis is as unique as the action, with well thought-out features that make it able to fit just about any shooter who would drop down behind it. The target stock is fully adjustable for cheek height, length of pull and recoil pad height, so getting comfortable behind the stock is never an issue. The stock adjustments are probably one of the better designs I’ve seen, with easy-to-turn thumb wheels that adjust the cheek piece height and length of pull. What I really liked about the thumb wheels is the ball detent that keeps the wheels from turning under recoil and gives the shooter a tactile indication when making adjustments. Like many aluminum rifle stocks, the AR-31’s chassis uses a standard AR-15 grip, in this case a Hogue grip that was very comfortable and provided adequate texture. The great thing about using the AR-15 grips is that it can be easily changed out to another one in just a few minutes if the shooter doesn’t like the Hogue grip. Most people don’t pay much attention to a stock’s forend, but I found it to be surprisingly comfortable in the hand, and the flat bottom would be well suited to shooting off a barricade or other support.

Shooting the AR-31

The AR-31 proved to be very easy to shoot out to 300 yards with superb accuracy and smooth feeding from the AR-10B magazines. Even though the Nightforce scope wasn’t optimized for this type of rifle, the fully adjustable target stock allowed me to easily get into a comfortable shooting position.

For the actual shooting portion of my evaluation, I wasn’t able to do the extensive range work that I had hoped for because of the fierce winter storms that had dumped snow on the Mid-Atlantic region. Luckily, a break in the winter weather allowed Peacemaker National Training Center to open some of their ranges for the first time in weeks, so I was able to finally get some much needed range time.

I had no trouble at all getting set up behind the AR-31 to run through some dry fire drills, thanks the adjustable cheek piece and recoil pad. Even with a Nightforce 2.5-10 in a LaRue mount, I had no trouble getting the perfect sight picture when behind the gun. Typically, before I send any live rounds down range, I run through some dry fire drills to get warmed up. I believe that dry firing is an invaluable training technique that improves the relationship between the shooter and the rifle and helps work out any kinks in a rifle’s set up.  I felt that the single-stage trigger was a little on the heavy side for my liking, but at a consistent four-pound break it was still certainly acceptable for a tactical rifle. The trigger broke crisply with no detectable creep and very little over-travel. I also noticed while manipulating the bolt that it seemed to just glide back and forth in the action while the floating bolt head locked up solid.

I first got the rifle on paper with some old soft-point hunting ammunition but I used the Remington Premier Match to get a better idea of how the rifle would shoot. The shot that’s up at 11 o’clock was the first round to get sighted in with match ammunition and from there it was a simple correction to bring me down to center. I easily put three in the center dot and then blew the very last shot by pulling it way out into right field, however the 20+ mph winds may have had something to do with it.

Peacemaker National Training Center has numerous ranges for everything from pistols to 1000-yard rifles, and Independence Range offers steel and paper targets from 50-300 yards. For this test, I was able to secure some Federal Gold Medal Match as well as some Remington Premium Match ammunition to try to wring every bit of accuracy that I could from the rifle. I placed a target at 100 yards and initially got the rifle on paper with some spare 150 grain soft point ammunition that I had sitting around. Once I knew I’d be able to hit paper, I got a better zero using the Remington match ammunition. The results were very promising, but winds that were in excess of 20 miles per hour made the going a little rough.  The rifle undoubtedly performed the best with Federal’s 168 grain Gold Medal Match ammunition with five-shot groups that were essentially one hole.  The Federal 175 grain Gold Medal Match didn’t do as well as I was hoping, but I believe it had more to do with the high winds and conditions down range than with the rifle.

The rifle loved the Federal 168 grain Gold Medal Match ammunition, turning in two very respectable 5 shot groups at 100 yards. The first group on the left comes in at just under .9 MOA, however that first shot at the top of the diamond ruined it all. The second group on the right was when I was able to settle down a bit and comes in at about ½ MOA. Federal 168 grain Gold Medal Match is arguably the standard for accuracy testing in a .308 and is used by numerous police departments nationwide for obvious reasons.

Shifting out to the range’s 300 yard steel, it was almost effortless to ring steel again and again, even in the high winds. Unfortunately, the steel had already taken quite a few impacts by the time I got there, so there wasn’t really a way to determine the group size on those targets. However, if I put the crosshairs on the right edge of the target, the right edge would swing back as the bullet impacted, so that indicated to me that the accuracy was surely there. The AR-31 fed smoothly from the AR-10B magazine, and not once did I have any trouble with rounds binding or jamming inside the magazine. Another advantage to the AR-10B magazines is that it gives the shooter a pretty good range of magazine capacity options all the way up to 25 rounds. Now somewhere, someone would probably ask what is the practicality of having a 25-round magazine in a bolt gun? It’s a purely rhetorical question, but there have been some match stages at Peacemaker that have required up to 15 rounds to complete the stage. Unless the person is running a semi-auto rifle, this means that the shooter is going to have to reload their rifle at some point, which costs time. An AR-31 with either a 15- or a 20-round magazine would have enough capacity for the shooter to engage all of the targets without worrying about reloading until the end of the stage. Of course, the 5- and 10-round Armalite magazines are more practical for most applications and they cost roughly half what some magazines that are used in bolt action rifles cost.

The more I shot the rifle, I really started to appreciate a couple of the features that aren’t commonly seen on precision rifles. One of those is a bolt hold-open feature that locks the bolt to the rear once the magazine is empty to let you know you have to reload. This is a useful and practical feature because there has been more than one occasion when I watched a shooter close the bolt on an empty chamber because he thought he had one more round. The only real downside that I can see to this is that it makes it next to impossible to single feed rounds quickly by dropping them through the ejection port. The side magazine release was another interesting feature that’s not seen on most rifles but is more or less a necessity when using the AR-10 magazines. Regardless, it makes magazine changes or unloading the rifle safe, intuitive and easy if familiar with an AR platform.

A 10 round AR-10B magazine (Right) is next to a standard 10 round AICS magazine to show the size difference between the two. Both are made from steel carry the same number of rounds but the AR-10B magazine is only a little wider and much shorter. A 15 round AR-10B magazine would probably be about the same dimensionally as the AICS magazine.

If there is one thing left to be desired on this rifle, it is the safety, which I felt was too hard to actuate at times. I appreciate its simplicity and function, but it wasn’t something that I could see a shooter easily flicking back and forth with a fluid movement like some other safety levers. Sometimes I found that I had to pull back on the lever and then try to flick it over at the same time to get it to work. I think part of the reason may be the cam angle that the lever has to overcome before it can slide to the opposite position. The other reason is that when you actuate the safety lever it is pulling back on the fairly substantial firing pin spring in order to engage or disengage the safety. I will admit though that my test is just a sample of one, so it may not be true for other AR-31 rifles and it may just require some break-in.

Easy Maintenance

Bolt-action rifles typically don’t require the extensive maintenance that semi-automatic rifles do, and the AR-31 is no exception. That being said, Armalite has integrated a couple of features into the rifle that make the task of cleaning and maintenance a little easier on the end user. The Remington 700 bolt, for example, requires a special tool in order to disassemble it for maintenance and then reassemble it again. The AR-31’s bolt doesn’t need any tools, as it can be easily disassembled when the safety lever is in the “Safe” position by unscrewing the bolt shroud. The bolt comes apart in to its three main components, the firing pin assembly, bolt handle and the bolt body, so that the end user can perform whatever maintenance is required. Another handy feature that helps make cleaning easier is a pass-through integrated into the cheek piece that works as a cleaning rod guide when aligned with the bore. However, because of the distance that the cheek piece is away from the action, I would imagine that an extra-long cleaning rod would be required to ensure the front of the rod clears the muzzle. It is a well thought-out feature though, and if the shooter wanted too he could still use a universal bore guide in the action as an added measure to keep the rod in line.

The AR-31’s muzzle brake is a scaled down version of the one used on the AR-30A1 rifle.

Final Thoughts

In my time spent with the Armalite AR-31, I appreciated its ruggedness, accuracy and over-engineered qualities, which brings me to one of its downsides, its weight. For a rifle chambered in a short action cartridge, I felt that it was a little on the porky side, but that weight can also work in your favor to help tame felt recoil. This isn’t the only heavy .308 out there though, as I’ve seen some other factory-built precision rifles and some custom guns weigh as much or more than the AR-31, so it’s a bit of wash. Are there other improvements I would like to see made to the rifle? Sure, I’d like to see a folding stock option down the road and the ability to install quick- detach mounts (aka flush cups) in addition to the standard sling swivels. Other than that, there really isn’t a lot bad to say about the rifle, and at the range it spoke for itself, ringing plates and stacking rounds one on top of another.

AR-31 Profile Left Side

When I first got the rifle, and even now, I believed that this rifle would be a viable choice for a police department looking to outfit their marksman/observer teams. Federal 168 grain Gold Medal Match ammunition is arguably the most common ammunition in use by police departments all across the nation, and this rifle loved to stack them inside an inch at 100 yards. The extended base allows night vision systems to mount in front of the day scope, and the threaded muzzle means that a suppressor can be added for signature reduction, making it effective day or night.  Of course, all of the things that make it good for a police department can also make it good for the hobbyist who wants rugged reliability and precision for predator hunting or competition. After using this rifle, I can honestly say that I wouldn’t be offended having this one sitting in my safe.

Ian Kenney is an avid firearms enthusiast and owner of ShootingVoodoo.com, a website dedicated to sharing information on multiple firearms topics.