The United States is the single largest civilian firearm market on earth. And within that market, one rifle reigns supreme: The AR-15. And for good reason. It’s pretty much everything you could possibly want in an everyman’s rifle. Available in everything from coyote to moose calibres, weighing no more than your average bolt-action rifle, having less felt recoil, providing superb accuracy, and highly modular, it probably is the best rifle of the 21st century. And not surprisingly, because of all that popularity, it’s cheap too.

As a result of this momentum, the majority of North America’s rifle manufacturers have been relatively recalcitrant to develop new designs that depart from the AR-15 platform, lest they give up ground to a competitor. Hence, we Canadians are often forced to look abroad or to niche markets to find a similarly modern semi-automatic rifle, and oftentimes the things we find end up costing far more than an AR-15 ever would. The Bushmaster ACR DMR is one such rifle.

Created by firearms accessory titan Magpul and initially known as the Masada before being licensed to Bushmaster, the ACR has its roots in the early years of the 21st century; when large firearms manufacturers were still optimistic that the venerable M4 would be replaced by a more modern rifle. But, like the AR-15 in the civilian world, the M4 was (and remains) too deeply ingrained in the military machine to be uprooted.

As a result the ACR and its chief competitor, the FN SCAR, were forced to turn to smaller procurement markets for their success… special operations and foreign forces. Unfortunately for Bushmaster though, the SCAR became the preferred non-M4-pattern rifle of most US special operations forces, while the ACR had to go all the way to Poland to find success with the Polish Military Intelligence Service known as the Służba Wywiadu Wojskowego, or SWW. There, the ACR has been so well loved that the Polish firearms manufacturer Radom has commissioned a new ACR-based modular rifle known as the Radom MSBS, for issue to all members of the Polish military.

Unfortunately, the relative lack of military success has had a detrimental effect on the amount of attention and expenditure lavished on the ACR, and what was once supposed to be an extensive family of rifles with numerous caliber conversion kits has turned into just a handful of models carrying relatively large price tags due to their rarity. And for Canadians, the frustration has been two-fold, as the ACR platform is non-restricted but rifle availability was limited to models with 16″ barrels. As a result all ACRs were restricted upon import due to their barrel length.

That meant anyone desiring to actually own a non-restricted ACR needed to get a new barrel fitted by a Canadian gunsmith; a relatively time-consuming and expensive process. Which is precisely why the debut of the Bushmaster ACR DMR, with a factory-fitted 18.5″ barrel, was so compelling when it broke cover in 2014. Unfortunately, again the preference for the AR-15 and M4 pattern of rifles impeded the ACR’s progress, and a combination of war efforts in the Middle East and a civilian penchant for ever-more AR-15s conspired to keep the ACR DMR out of production until the fourth quarter of 2016. But it’s here now.

What is the ACR DMR?

For those unfamiliar, the ACR is a piston-driven highly modular rifle platform utilizing conventional STANAG-pattern magazines, and offering almost unparalleled ambidexterity and flexibility. The rifle itself is comprised of five major components: The stock, fire control group, receiver, handguard, and barrel. Unlike the AR-15, all of these components can be replaced with any other available component in mere seconds with no tools. The receiver, stock, fire control group and handguard are all retained with simple push pins while the barrel is secured to the receiver by a threaded collar. Even torqueing the barrel in place requires no tools, as the barrels incorporate integral folding handles on the threaded collar, which itself is prevented from backing out by a built-in ratcheting system.

In the past ACRs have been available with either a fixed or folding stock, both of which incorporate particularly brilliantly adjustable cheek risers, while the latter also adjusts for length of pull. The ACR DMR, however, uses a Magpul PRS2 stock specifically designed for the ACR. With threaded adjustments for both length of pull and comb height, this stock allows for fine adjustment in both directions, but sadly does not incorporate the conventional PRS stock’s railed lower portion; precluding the use of a stock-supporting monopod.

Moving forward, the ACR DMR borrows both the fire control group and receiver components from the standard ACR, but fills the former with a Super ACR trigger from Geissele Automatics. A very smooth two-stage trigger with listed pull weights of 2.5 pounds for the first stage, and 2 pounds for the second (for a total pull weight of 4.5 pounds), beyond being a boon to accuracy this trigger’s inclusion in the ACR DMR right out of the box is not an insignificant feature: If you were to buy one separately you should expect to pay $400 for the privilege!

Which brings us to the ACR DMR’s most important feature; the barrel. Measuring 18.5″ long, this wonderful piece of forged stainless steel is notable for a few different reasons, the most important of which is obviously its fulfillment of the Canadian firearms act’s requirement that non-restricted semi-automatic rifles possess a minimum barrel length of 18.5 inches.
But there’s more to it than that. First off, it’s heavy… almost ridiculously so. Measuring 0.98″ across from the breech to the op rod guide, 0.90″ to 0.85″ between the op rod guide and the gas block, and 0.73″ from the gas block to the muzzle device it is one of the heaviest barrel profiles you’ll find on such a rifle. Also, although the bolt is marked “multical,” that beefy barrel is chambered in 5.56 NATO. The rifling is cut to match the current standard for most 5.56 NATO rifles, with a 1-in-7 inch twist rate.

All the aforementioned components can be disassembled quickly, and with no tools. The two pins located where the stock joins the rifle hold the receiver and fire control group to the stock. Pull the topmost pin and the receiver and barrel assembly hinge downward like an AR-15’s upper receiver. Slide the lower pin out and the stock can be lifted free. Ahead of the magazine well, the front take down pin secures the fire control group to the upper receiver and barrel, and just ahead of that pin is the pin that secures the handguard to the upper receiver. Pulling that pin and removing the handguard reveals the handle on the barrel that must be pulled down and rotated to unthread the barrel nut and release the barrel. Overall, it’s brilliantly designed.

ACR DMR First Impressions

The ACR DMR arrives, like so many other premium Bushmaster firearms, in a relatively staid Bushmaster box containing (in grand Russian nesting doll fashion) a Bushmaster-branded Flambeau rifle case. And inside that is the ACR DMR, safely bagged in plastic, the ubiquitous and always unloved cable rifle lock, and one 5-round Magpul Pmag.

And undoubtedly, the first thing anyone will notice when they pull the DMR out of its case is the overall weight of the thing. Out of the box, sans sling, optic, magazine and ammunition, our test rifle tipped the scales at ten pounds even. As pictured here, with a Bushnell Elite Tactical 1-8.5x24mm optic in an American Defense Manufacturing Recon mount, and a Blue Force Gear VCAS sling, the entire thing weighs 12.5 pounds; definitely on the portlier side of things.

Handling the ACR DMR will feel oddly familiar to anyone that’s spend much time behind an AR-15; the pistol grip, safety, and overall dimensions being somewhat similar. But we say oddly because while it feels akin to an AR-15 when you’re behind it, there’s a few features that we find dramatically improve upon the AR-15 experience. First and foremost is the charging handle. Positioned forward and high on the action like a SCAR’s, but being both non-reciprocating and capable of functioning as a forward assist due to its clever design, it comes easily to hand and is easier to work than an AR-15’s charging handle. Furthermore, swapping it from one side to another is as easy as depressing a latch atop the rifle with the nose of a bullet, pulling the handle out and re-inserting it from the other side. We just wish the handle itself were slightly larger.

Likewise, we also love the controls for their similarly well-thought out nature. The bolt release is a pair of paddles on the front of the trigger guard; easily depressed by either the trigger finger or a thumb upon reloading. The magazine release is both oversized and ambidextrous. Rounding out the lefty-friendly nature of the ACR is an ambidextrous safety.

Not surprisingly, for a rifle that’s predicated on the notions of flexibility, ambidexterity, and modularity, the ACR DMR also features an almost ridiculous number of small, but useful additional features. First off, the pistol grip contains a secure CR123 battery storage tube. The grip panels cast into the pistol grip and magazine well are actually tiny Magpul logos superimposed on a pebbled texture and are wonderfully grippy. The gas cylinder is capped by a regulator that allows the used to select the appropriate gas setting for unsuppressed or suppressed operation (dare to dream, right). And the rifle has no less than seven sling points baked into its design; five quick-release sling points and two fixed sling points on the stock that can be swapped from one side to the other as the owner sees fit. Interestingly though, on our test rifle, the two quick-release sling points fitted to the fore-end were installed backwards; a problem easily rectified with five minutes and an allen wrench.

Likewise, we also must mention that although the charging handle is in a fantastic position in terms of manipulation and leverage, it does travel through a not insubstantial amount of space on the handguard. In fact, we had initially mounted our optic in a standard-style mount, but the forward scope mount clamp did not allow enough room for us to cycle the charging handle fully rearward. Also, although we’ve not installed any such devices, we suspect things like PEQ-15s, lasers, and lights would all restrict either access to, or movement of the charging handle.

Shooting the ACR DMR

Now, it’s at this point that we must point out that this is a non-restricted black rifle, which already makes it one in a relatively small subset of rifles, but the ACR goes even farther by being a very specialized rifle; it isn’t called a DMR for nothing. This is intended to be used in the role of a designated marksman’s rifle. Hence the heavy, but accurate barrel and heavy, but adjustable stock. We did most of our testing off either a lead sled when trying to test the rifle’s mechanical accuracy and off a shooting bag for the rest of our testing. It’s not something you’re going to want to run around doing drills with and holding in an offhand position for long.

But if you’re looking for something that will allow you to take advantage of the limitless ranges at which you can shoot on Crown land… well, this may be your rifle. Perched atop our well-seasoned Vertx range bag (which makes an excellent rifle rest, by the way) the ACR DMR was a treat to shoot. The Magpul PRS is a fantastic piece of equipment, and with its adjustable length of pull and comb height allowing us to get comfortable behind the gun, we were able to string together groups of comparable size to those that we shot off the lead sled. And that’s a good indication of the rifle’s sort of intrinsic performance insofar as how well it marries man and machine.

Furthermore, the level of comfort the rifle provides and its weight both make shooting not only easy, but pleasant. Although we (sadly) can’t stick the appropriate AAC suppressor on the AAC 51T flash hider/suppressor mount, the 18″ barrel does a reasonable job of quelling as much of the 5.56’s report as possible… and moves it farther from the shooter’s ears. The Geissele trigger is, in a word, excellent. We’ve always been partial to good two-stage triggers, and this is a good one; there’s a tiny bit of creep at the beginning of the second stage but it’s barely noticeable and will probably go away with more use. The pull weight is ideal. The first stage is light but positive; you know you’re pulling through it and the beginning of the second stage is definitely not something you’ll notice. In other words, it’s like all good two-stage triggers in that it takes a small degree of effort to get through the first stage, and a similar amount of effort to break the second stage. And the reset is very positive, and long enough to get you right back to the same position as your first shot was taken from… and as we all know, consistency is the key to accuracy. On the other end side of the coin, the trigger’s not so light nor effortless that we were ever concerned that we’d pull a shot off before we expected it; there’s a reason 4.5 pounds is generally considered the sweet spot for accurate but practical trigger weights.

Speaking of weights, there definitely an upside to the rifle’s not insubstantial weight. Weighing as much as a .308 but only shooting 5.56 means there’s almost no recoil, so watching bullet trace and impact is much easier than on a lighter rifle, which in turn means more accuracy.

Overall, the impression of shooting the ACR DMR is one of capability; the rifle’s so easy to set up and shoot that you can concentrate on your shooting technique. You needn’t adopt an unnatural position to get behind the gun. You needn’t break your shooting position to load the next round. You needn’t anticipate any significant recoil. You don’t even need to remove your hand from the grip to operate any of the controls, regardless of if you’re right- or left-handed. Simply concentrate on breathing, trigger control, and sight picture.

In terms of reliability and performance, the ACR has proven to be one of the most reliable rifles we’ve ever tested; it’s literally never not worked. Now, in all fairness, we’ve had other rifles that have proven to be 100% reliable… but we’ve never shot a rifle with as many different varieties of ammunition or magazines as we have the ACR DMR.

We’ve also never shot a rifle in any many varied conditions as this rifle. From 10 degrees above zero and dry to -15 and snowing, it’s fed no less than 8 different kinds of magazines through it, with well over a dozen different kinds of .223 and 5.56 ammunition and it’s done it everywhere from clean gun club shooting benches to dirty, muddy, snowy back roads. So when you consider all those variables, it’s pretty impressive. In the two short months that we’ve been testing it, the beefy Bushmaster has given us utter confidence in its reliability, and we expect it to continue to do so.

But if we’re honest, we expected as much from the ACR DMR; being a premium piston-drive gun there’s no reason to think it’d ever choke. But the ACR doesn’t have the best reputation for accuracy. Due to the nature of its quick-change barrel system, it’s hard to manufacture such a rifle on a large scale and do so with a high degree of accuracy, and most ACRs are known for being “battlefield accurate.” In other words, 2-4 MOA, or perhaps slightly better. The DMR is not like other ACRs though, evidently.

ACR DMRAlthough accuracy with many of the bulk ammunition varieties typically ran around 2 MOA, the DMR responded very well to ammunition that makes use of the barrel’s fast twist rate. Longer, heavier bullets ranging in weight from 69- to 77-grains typically worked well, as did the newer forms of factory ammunition specifically directed at semi-automatic rifles with faster twist barrels, like Barnes’ lead-free 52-grain zinc-core RangeAR ammunition.


The Bushmaster ACR DMR is many things. Accurate, reliable, heavy, and expensive. But it’s also rare. As previously discussed, ACRs remain a relatively uncommon rifle in all circles, and with only 100 ACR DMRs having come to Canada in the first shipment these particular rifles are unlikely to ever become common.
And although Bushmaster’s importer, Gravel Agency, is looking forward to additional shipments throughout 2017, the combination of the rifle’s niche appeal and $3,399 retail price relegate this rifle to somewhat exotic status.

But if you happen to be in the market for something non-restricted, that’s not only capable of, but rather particularly well suited to longer range shooting, this is a great rifle. So great, in fact, that we lightened our own wallet in order to purchase the rifle pictured here. That makes it 99 out there and counting for now…