One of the greatest strengths of the firearms industry is its constant innovation—few if any are ever satisfied with the status quo. While much of this is driven by sales, the operator’s perceived needs also factor into innovation. This is especially true of our most elite military forces.

As each deployment is concluded, these highly trained professionals evaluate what may work better on the next. This is anything but an academic exercise, as better equipment can easily equate to lives saved. Change can start with something as simple as a team member modifying a piece of gear, or with an inquiry that makes its way to contractors working closely with these forces. In some cases these modification requests are officially contracted; fortunately in others, the modifications make their way to the general market, often with a slightly different application for the civilian end-user. One such venture is the 300 Blackout cartridge.

Short .30 Caliber
Many have attempted to create a larger cartridge that will work in an AR rifle designed for 5.56mm NATO. Most tried to approximate the ballistics of the 7.62x39mm cartridge but with added accuracy. Several such attempts have been quite successful. Some cartridges use smaller bullets, like the 6.5 or 6.8mm that provide superior accuracy and better ballistics. But these cartridges also require different bolts and magazines.

The 6.8 SPC may be the best example. It enjoys solid success and broad appeal among users. Other cartridges use .30 caliber projectiles with the same limitations of the 6.8 SPC. However, making a .30 caliber bullet function with the .223 parent case has not always worked, and those that do never seem to garner support from the market. Moreover, broad acceptance within the police or military world requires buy-in of the cartridge from the major ammunition manufacturers. But one round that is gathering some serious steam is the 300 Blackout.

It all started with the military’s need to create a .30 caliber cartridge that would operate in a standard M4 platform. The military needed to use mil-spec 5.56mm magazines already in inventory, and the magazines needed to be loaded to capacity. Early attention was spent on subsonic loads. The idea was for a reliable, suppressed, short-barreled entry weapon with good penetration. Often the venerable HK MP5 SD was cited as an exemplar. (Having used one for years on a SWAT team, I can attest that its advantages for entry are many.) With nearly silent operation the MP5 SD was compact, lightweight, incredibly reliable and precision accurate, but with the platform no longer supported, the military wanted an AR that would approximate it. The supersonic loads were to match 7.62x39mm ballistics as closely as possible.

Advanced Armament, working in conjunction with Remington, developed the 300 Blackout, which met most of the military’s requirements rather nicely. With properly set up, suppressed short-barreled rifles, the subsonic rounds run reliably, and full-power loads often exceed 7.62x39mm ballistics, demonstrating far superior accuracy (especially out of a 16-inch barrel). Many companies are now making 300 Blackout rifles, barrels and, most importantly, ammunition, so support is improving rapidly. One such rifle is the ATI ARcane in 300 Blackout.

Gun Details
The American Tactical Imports (ATI) ARcane rifle in 300 Blackout begins with a forged 7075-T6 aluminum lower, an A2 pistol grip, a six-position buffer tube and an M4-style stock. Internals, including the trigger, are mil-spec. ATI uses a 16-inch barrel with a 1-in-7-inch twist rate and a Melonite finish. A Head Down PVX muzzle brake caps the 5/8x24mm threads. The gas system is carbine length and capped off with a slim gas block. The mil-spec Carpenter 158 steel bolt and 8920 steel carrier provide for reliability and strength. The 13-inch Head Down Provectus rail has a 1.8-inch inside diameter, which allows the mounting of over-the-barrel suppressors. Cutouts assist in heat dissipation and keep the weight under check. Much of the forend is smooth, so no rail covers are required, making for very comfortable shooting from unsupported positions. Locking tabs prevent rotation under hard use. Short rails at the forward portion of the rail accommodate lights and other accessories. Non-rotating QD sling mounts accept push-button swivels.

For testing, I used a Leupold MR/T 1.5-5x tactical scope with a lighted 300 Blackout reticle and 30mm tube. The standard M2 knobs with a zero stop were flat and secure. The lighted reticle has seven intensity settings with an off-position in between each setting that enables fast activation and deactivation. The Leupold Mark 2 IMS 30mm integral mount kept the scope in place. For stability I attached a BlackHawk bipod, which connects to the bottom rail with ease and works well with most AR rifles.

Range Time
The 300 Blackout’s accuracy has been pretty stellar, especially with match ammunition. Even my short barrel was incredibly accurate with the cartridge. Not surprisingly, the ARcane was quite accurate too. Remington 125-grain OTM had the best group at 0.75 inches. This probably doesn’t make it the best duty round, but it is precision-rifle accurate and suitable for military operations or long-distance shooting. The ARcane shot everything else well within the acceptable limits of a duty rifle.

Moving out to 300 and 500 yards, the ARcane worked very well. Loaded up with the Remington 125-grain match ammunition and mounting a Leupold reticle, the rifle put me on steel at both ranges. With a storm coming in, there was a full-value wind with gusts in the teens. With the wind holds in the scope, the shots came very close to point of aim. It took a few shots to get completely dialed in, but that was as much about the trigger as the scope. Standard military triggers are a bit crunchy and anything but precise. A precision trigger would be a huge help, especially at longer ranges. Most agencies will never see 500-yard targets, but other applications may. At 300 yards and in, it was very easy to stay on target.

D&H magazines have developed quite the reputation in the aluminum magazine business, and the one provided worked fine. I had recently acquired a set of Gen 3 PMags, so I used those most during testing—they worked perfectly. (Previous generations of PMags had rather spotty success in this caliber, with the internal rib of some of those magazines occasionally interfering.) Those PMags tested in other 300 BLK models have met with the same success. Most of the aluminum mil-spec magazines seem to work without issue too (the Lancer magazines are also flawless).

Subsonic rounds are not high on my list, but given that the ARcane was the first 16-inch rifle I could test with them, I threw subsonics into the mix. Everyone who makes and sells 300 Blackout says it will work in subsonic. Well, not for me so far. The ARcane ran the 208-grain Hornady .300 Whisper, but barely, and it did not cycle the 220-grain loading at all. Suppressors can certainly change this dynamic, but it will be quite dependent on the suppressor. I have yet to find a rifle or rifle-accessory combination to make the transition to subsonic with duty reliability. But I am uncertain whether there are any circumstances when someone would need to do this. It can be done, however. In my experience, you will need an adjustable gas block and a spring or even a buffer change—nothing that is useful in the field. Nevertheless, the ARcane’s accuracy in subsonic is pretty astounding, especially at any practical range.

The muzzle brake worked fine—loud, but not overpowering like some. Recoil was minimal with very little dust coming up from prone. I’m not a real fan of muzzle brakes, my preference for having a solid flash suppressor remains. Since the ARcane has standard threading, a Vortex or similar flash suppressor could be installed easily. For those with quick-detach suppressors, those will work as well.
When it comes to choices in 300 Blackout, proven controlled-expansion rounds are already on the market, making them suitable for close-quarters work. Along with its VOR-TX loading, Barnes is making an excellent Military/LE 110-grain TTSX. Several companies are starting to load with this bullet, which has proven accurate in the RTBA (Right to Bear Ammo), as well as in CorBon and DoubleTap loadings. Hornady’s .300 Whisper 110-grain V-MAX is a confirmed expander in other .30 caliber rounds, and it produced excellent accuracy during the test. Remington also makes an excellent 125-grain AccuTip round—it is just really hard to find. Either way, if support for the 300 Blackout continues, the options will only get better.

Final Notes
The 300 Blackout is really catching on, with new ammunition companies steadily coming on board. Solid duty and defense ammunition is available right, in most places, now with costs commensurate to those of many 5.56mm rounds. Conversion can be accomplished with a simple barrel change, and most standard magazines work just fine.

ATI’s ARcane is a solid offering in this caliber. It proved reliable, accurate and handy while working around real-world obstacles. And with a price of $999, the rifle comes at a fairly reasonable price. If your operational need puts 300 Blackout on your radar, take a look at ATI’s ARcane. For more information, call 800-290-0065 or visit

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