Exemplary Ergonomics
The ACR’s construction and design are rugged and reliable, but they are not revolutionary. Most of the components and operating principles, such as the heavy bolt and indirect gas-impingement operating system, are designs with proven histories, but what really sets the ACR apart from older designs are its ergonomics. For example, both the magazine release and the bolt stop buttons can be worked with the trigger finger, and they are also completely ambidextrous. Mirrored magazine release buttons can be found on both sides of the lower receiver just above the front of the trigger well. The buttons are large, square and grooved for easy activation and fenced to reduce the chances of their being accidentally depressed. The bolt stop release is of a design first seen on the Robinson Arms XCR. Located between the front of the trigger well and the rear of the magazine well, the bolt stop releases have a stepped contour that leaves them raised at their centers. Pushing up on either button engages the bolt stop. Pressing down releases it. Additionally, the rising follower of an empty magazine automatically activates the bolt stop, so the bolt stays open after the last round is fired. The ambidextrous safety lever can be worked with the thumb of the firing hand. The safety lever rotates easily throughout its 90-degree travel without binding, yet it positively engages both the “safe” and “fire” settings.

One change in the layout of the controls from the original Magpul Masada is the location of the charging handle. Much like that of the H&K MP5, the non-reciprocating handle moves in a slot running along the top half of the fore-end. The polymer handle has a grooved face and is reversible for left-handed use. The handle is hinged, which improves its performance as a forward assist in the event that the bolt should fail to fully seat into battery. Bushmaster representatives tell me that a universal variant of the charging handle that extends out both sides of the receiver will be available as an accessory. Positioning the charging handle in front of the action makes it easy to work it with the support hand, so the shooter doesn’t have to re-establish the grip of his strong hand; this allows the user to keep his head on the stock and thus keep his eyes on target as he works the bolt to reload or reduce a stoppage.

Other ergonomic touches include grip-enhancing texturing on the side panels of the magazine well and pistol grip. The stocks of both the Basic and Enhanced ACRs have a Quick Detach sling coupler near the joint of the heel and the comb. The QD coupler on the stock can be swapped to the opposite side if so desired. QD couplers are also found forward, just above the hinge pin where the barrel and the upper and lower receivers join the trunnion and on the vertical walls of the free-floating fore-end just to the rear of the gas block. The Enhanced ACR comes with a push-button sling from Blue Force Gear that snaps right on (the Basic ACR does not come with a sling).

The ACR’s sights have not been overlooked, either. Both the Basic and Enhanced ACRs come with Magpul MBUS back-up sights. They fold down when not in use, but wings on both sides of the front and rear sights can be quickly deployed with the thumbs of the firer’s shooting and support hands. The rear aperture is screw-adjustable for windage and the front post can be adjusted for elevation with the tip of a bullet or a special purpose tool. The rear sight has two apertures. The smaller aperture is optimized for 100 to 300 meters, and the larger aperture is intended for what the manual calls “Short Range,” or out to 100 meters.

About the only ergonomic disappointment may be the integral pistol grip. It’s raked at a good angle and its size and contour should be compatible with most hand sizes, but it’s not hard to imagine something better. Representatives from Remington tell me that they are developing an aluminum lower receiver for the ACR. Its pistol grip will be a separate component and thus easily replaceable.

Rugged Performance
When word spread that the bore wasn’t chrome-plated, it led the shooting public to suspect that endurance testing had been given short shrift. In reality, nothing could be further from the truth. Remington, Bushmaster and Magpul collaborated throughout the development of the gun. Given that the military version of the ACR is intended to compete in upcoming military trials as an alternative to the M4, it was designed for maximum durability and reliability. Extensive environmental and endurance testing is much of what delayed its release.

Toward that end, Remington developed a proprietary finish for use in both the Remington and Bushmaster ACRs. Impregnated with a dry lubricant, the new finish will be applied to the inside of the bore and to all of the working components of the gun. Remington claims its new finish resists corrosion and doubles the service life of the bore. Additionally, it dispenses with the need for any additional lubrication. Needless to say, this limits the accumulation of carbon- and environment-based fouling.

The gun is made without an ejection port cover. Keeping dirt out of a self-loading firearm was seen as a vain effort; instead, the ACR was designed to shed any dirt and sand that gets in. Looking down through the ejection port, one can see a gap between the bolt carrier and the receiver wall. Gaps like this are meant to aid the egress of sand, mud and water.

Shoot It And Shoot It Some More
The trigger of the ACR is pretty much identical to any standard single-stage unit you’ll find in an AR-15-style rifle. About the only difference is that it is housed in a removable chassis rather than mounted on pins in the lower receiver. I’m told that Remington and Bushmaster plan to make two-stage units available in the near future. The trigger of my sample gun broke at slightly more than 6 pounds of pull weight. Trigger travel was commendably smooth, there was no stacking and minimal overtravel.

For accuracy testing I mounted a 6X Leupold M8 Compact with adjustable parallax in a steel base and ring combination mount from ArmaLite. Accuracy results compare favorably with most AR-15-style tactical rifles I’ve tested in the past. Given the barrel’s 1:9-inch twist rate I stuck to loads with bullets weighing 55 grains or less.

Remington supplied a prototype 6.8x43 mm barrel, bolt and magazine for function testing, but time constraints kept me from performing a complete accuracy test in that caliber. I can say that the ACR retained its zeroes after caliber swaps and the gun functioned flawlessly in both calibers. There were no failures to feed, fire or eject.

It was in rapid-fire shooting drills that the ACR revealed its true beauty. All of the controls are within easy reach and engaged and disengaged without any binding or slop. The supplied Magpul PMAG 30-round magazines fed flawlessly, consistently engaged the bolt stop and dropped free of their own empty weight. The layout of the controls made for smooth reloads and rapid reduction of induced stoppages. As a southpaw, I was pleased that the ACR’s shell deflector kept ejected cases well away from my face.

Was the ACR worth the wait? To my way of thinking, the question is moot. Bushmaster didn’t tie up anyone’s money by taking orders it wouldn’t be able to fill or leave anyone hopelessly unarmed. The ACR also didn’t become obsolete or antiquated during the time it was in development. So I don’t see any point in judging the Bushmaster ACR on anything other than its merits. The gun certainly delivers on performance and handling, and given the speed with which one can change the barrel, it is certainly adaptable. Remington’s proprietary coating for the ACR that dispenses with the need for lubrication is certainly promising, but it is a feature that adds to the cost. Without it, the gun would be less expensive, but the last thing Bushmaster and Remington wanted to do was release a “beta” version of the ACR that didn’t perform like the real thing. The ACR is expensive, and certainly far more expensive than anyone expected, but it is also a one-of-a-kind rifle.