300 AAC Blackout Semi-Automatic AR-15 Upper from Advanced Armament Corporation


by Jeff Quinn

photography by Jeff Quinn & Boge Quinn

November 27th, 2011


YouTube Video





Click pictures for a larger version.


300 Blackout.



Remington factory ammo is readily available.



Barnes 110-grain TAC-TX bullet is designed especially for the 300 Blackout.



Atlanta Arms ammo.



Front sight is integral with the Knight's railed handguard.



DPMS lower has Timney drop-in match trigger.



3Bucc brass catcher.



DPMS lower is fitted with Ace skeleton buttstock.




The 300 Blackout cartridge has really piqued my interest. Similar in concept and performance to the 300 Whisper, which has been around for several years now, the Blackout takes the concept to a new level, with SAAMI (Sporting Arms and Ammunition Manufacturer’s Institute) specifications and readily-available factory ammunition.

The idea behind the creation of the 300 Blackout is to give a 30 caliber AR-based rifle, capable of subsonic sound-suppressed fire or full-power supersonic fire with ballistics comparable to the 7.62x39mm Russian cartridge. While there have been attempts at building reliable 7.62x39mm Russian AR-15 rifles, with varying degrees of success, the 300 Blackout does all that the Russian cartridge does, with much better reliability, while using standard 5.56mm AR magazines and a standard 5.56mm-sized bolt face. The problem with adapting the Russian cartridge to work in the AR is the shape of that tapered cartridge case, which requires a curved magazine for reliable function. The 300 Blackout has no such heavy taper, and works perfectly through any reliable 5.56x45mm AR-15/M-16/M-4 magazine, keeping the same magazine capacity as the 5.56x45mm cartridge. The Blackout cartridge succeeds in its goals of meeting 7.62x39 ballistics with full-power loads, and also of offering a reliable, quiet, and effective subsonic load for rifle or submachine gun use.

The 300 AAC Blackout is the product of development of the Advanced Armament Corporation (AAC). AAC is now part of the Freedom Group of companies, which includes Remington, Marlin, H&R, DPMS, Bushmaster, and others. While some in the industry object to these large corporations such as the Freedom Group buying up gun companies, the relationship among the companies in the group, along with the deep financial pockets of the mother ship, allows development of such specialized weapons such as the 300 AAC Blackout to come to market, along with the cooperation among the various companies to support each other in the endeavor. In the case of the 300 Blackout, AAC has coordinated with Remington Ammunition to develop and produce a reliable source of factory-loaded ammunition, and Barnes Bullets, which is also now part of the Freedom Group, has introduced into their new military/law enforcement line a bullet specially made to consistently expand at 300 Blackout velocities, and to feed reliably in the AR-15 300 Blackout weapons.

I was first introduced to the 300 AAC Blackout several months ago while on a visit to the Leupold & Stevens optics factory in Beaverton, Oregon. After a very interesting factory tour in the morning, a few other writers and myself got to spend the afternoon at the range with some of the Leupold personnel. One of the rifles that we fired was an AR-15 chambered for the 300 Blackout. Leupold has developed a special 1.5 to 5 power scope that has a dedicated reticle for the two current Remington factory 300 Blackout cartridges, with one side of the reticle having aiming points for the subsonic load, and the opposite side having aiming points for the supersonic load. It is a superb riflescope, which I had the opportunity to also use a couple of months later in South Carolina on a shoot with AAC and other members of the Freedom Group. At both events, the Leupold scope matched up perfectly with the trajectories of the factory Remington cartridges, but the distance tried was only out to about 225 yards. The scope is set up to be useful at close range and also out to several hundred yards. Hopefully, I can try out the Leupold on a 300 Blackout at greater distances sometime in the future, but I do not yet have one of those scopes here for a more thorough review. With both of those brief experiences, I was impressed with the 300 AAC Blackout, and was delighted when a sixteen-inch barreled upper receiver arrived here a couple of weeks ago. I already had ammo waiting, so I attached the upper to a DPMS lower which is fitted with a Timney match trigger and an Ace skeleton buttstock. This lower usually is mated to my Alexander Arms 50 Beowulf upper, and is perfect for working out the AAC Blackout.

Not having access to the special scope that Leupold builds for the Blackout, I mounted another fine riflescope; a Leupold Mark 4 4.5 to 14 power with illuminated mil-dot reticle. This scope is very versatile, and the mil-dots do double duty at estimating distance and also as aiming point holdovers at extended range. The illuminated reticle has a rheostat dial to adjust the brightness, and the glass has superb optical clarity. I fired the Blackout using the three factory loads available to me, along with a handload that used the Barnes TAC-TX 110 grain bullet loaded over 19 grains of Hodgdon H-110 powder. This load has not been pressure tested, and is not published in any load data manual. It worked very well for me, pushing the sleek Barnes bullets out the muzzle at about 2300 feet-per-second, with very good accuracy. The Remington sub-sonic load pushed its 220 grain bullet to 1028 fps at ten feet from the muzzle. The 125 grain Remington OTM load registered 2213 average fps at the same distance, and the Atlanta Arms Pink Tip clocked 2232. All accuracy and velocity testing was done at an elevation of 542 feet above sea level, with temperatures in the 65 degree Fahrenheit range, with a slight breeze and low humidity. The 300 AAC Blackout upper exhibited very good accuracy, as shown in the pictures, with every group fired grouping three shots into one and one-half inches or less, with five shot and even ten-shot groups doing almost as well. All accuracy testing was done firing from a solid bench using a Target Shooting, Inc. Model 500 rifle rest.

I had hoped to test the 300 AAC Blackout with my Tactical Solutions sound suppressor, but I could not remove the flash suppressor to do so. I tried to remove it, but seeing that I was going to likely damage the flash suppressor in the attempt, I stopped before making a mess of things. I did, however, fired suppressed 300 Blackout rifles in Oregon and South Carolina previously, and can attest to the fact that the subsonic ammo made almost no sound at all upon firing, and I could hear the bullet hit the target at 100 yards easily.

The 300 AAC Blackout is a superb cartridge for its intended use as a close to medium range fighting rifle, and should also work very well for hunting medium-sized game and predators. It is superior to many other AR-based weapons in that regard, and also superior to 9x19mm similar carbines, short-barreled rifles, and submachine guns. The Blackout offers more power with a better bullet design for increased effectiveness. The ability of the Blackout to use cheap, proven, and plentiful AR-15/M-16 magazines is a great advantage, along with a seemingly-endless variety of .308 inch diameter bullets.

With the technological knowledge and manufacturing ability of AAC, combined with the support of the other companies in the Freedom Group, it looks like the 300 AAC Blackout has a bright future ahead of it. AAC has already shown an affordable NEF single-shot as well as a Model 7 Remington bolt-action chambered for the 300 AAC Blackout cartridge. I had the opportunity to fire both, and they shot very well. The 300 AAC Blackout is a very efficient cartridge, with a much greater terminal effect than its diminutive cartridge case would indicate. Nothing is wasted in the case design, and it takes very little powder and muzzle blast to achieve the resulting performance of the little cartridge.

The 300 Blackout upper receivers and barrels are available now from AAC, and Remington and Atlanta Arms already has 300 AAC Blackout ammunition in full production.

Check out the 300 AAC Blackout online at www.300aacblackout.com.

For more information on the ammunition shown here, go to www.remington.com and www.atlantaarmsandammo.com.

300 Blackout ammunition is also available from www.pnwarms.com.

For a look at the extensive line of quality Leupold optics, go to www.leupold.com.

To order the Barnes TAC-TX bullets shown here, go to www.barnesbullets.com.

Jeff Quinn

NOTE: All load data posted on this web site are for educational purposes only. Neither the author nor GunBlast.com assume any responsibility for the use or misuse of this data. The data indicated were arrived at using specialized equipment under conditions not necessarily comparable to those encountered by the potential user of this data.  Always use data from respected loading manuals and begin working up loads at least 10% below the loads indicated in the source manual.

Got something to say about this article? Want to agree (or disagree) with it? Click the following link to go to the GUNBlast Feedback Page.



Click pictures for a larger version.




Author shooting the suppressed 300 AAC Blackout in Oregon.



Riza Tavares of Leupold shooting the 300 Blackout.



Cartridge comparison, left to right: 5.56x45mm, 6.5mm Grendel, 6.8mm SPC, 7.62x39mm, 300 AAC Blackout.



The 300 AAC Blackout (left) is comparable in power to the 7.62x39 (center) and the 30 WCF (30-30, right).



300 AAC Blackout uses a standard 5.56x45mm bolt face...



...and standard, unaltered 5.56x45mm AR-15 / M-16 magazines.



Leupold Mark 4 4.5-14 power illuminated scope was used for accuracy testing.



Leupold's custom reticle for the subsonic / supersonic 300 Blackout.



The 300 Blackout's accuracy was impressive.