300 Blackout: If the .223 Remington and the 7.62x39 had a baby

The 300 AAC Blackout — also called the 300BLK — uses a .308” diameter bullet and can be loaded with a great variety of projectiles ranging from 110 grain varmint bullets to 240 grain match bullets

The .223 Remington round was developed in the late 1950s after studies showed great lethality from a small projectile launched at high velocity. The idea was to create something akin to a piece of shrapnel that could be fired accurately from a rifle. 

Initial combat reports of the M16 and the then-new .223 Remington cartridge emerged early in the Vietnam War, telling of incredible wound trauma, organ and tissue damage, and even amputation. Many of these early reports were likely exaggerated — in order to sell more weapons — but the terminal ballistics of the .223 Remington are thoroughly documented. The small projectile is known to yaw, tumble, and break apart as a result of its high velocity. 

Original M16s used twenty-inch barrels to achieve this high velocity but the ongoing trend of shorter and shorter barrels has led to a loss of muzzle velocity, reducing the .223 Remington’s effectiveness. Cartridges like the 6.8 SPC — which fire heavier bullets — have been developed to compensate for the drop in bullet speed but none has gained more than a toehold for various reasons. This was true until Advanced Armament Corporation introduced the 300 AAC Blackout.

The 300BLK flanked by the Russian 7.62x39 on the left and the 223 Remington on the right. (PoliceOne Image)
The 300BLK flanked by the Russian 7.62x39 on the left and the 223 Remington on the right. (PoliceOne Image)

An Outstanding Choice
The 300 AAC Blackout — also called the 300BLK — uses a .308” diameter bullet and can be loaded with a great variety of projectiles ranging from 110 grain varmint bullets to 240 grain match bullets. This vast array of bullets is what makes the 300BLK an outstanding choice for the law enforcement officer. 

When loaded with light 110 grain or 125 grain projectiles, the 300BLK compares very favorably with the combat-proven Soviet 7.62x39 cartridge and offers a 10 to 15 percent increase in energy over the .223 Remington. When the 300BLK is loaded with heavy subsonic bullets and equipped with a noise suppressor it is right at home as an entry/CQB cartridge and delivers 50 percent more muzzle energy than a 147 grain 9mm subsonic round. 

The 300BLK offers all this in one weapon without changing anything other than the ammunition in the magazine. 

Ammunition suitable for plinking and practice can be obtained from multiple sources, including loading your own. Much of this ammo is made from cut down and reformed .223 Remington brass and is loaded with either light varmint bullets or military surplus bullets. 

Ammunition suitable for defense and duty is being produced by Remington, Hornady, Nosler, and Barnes among many others. On the subsonic side of the house, shooters can buy new ammo from Remington and Hornady. Federal is working on an inexpensive subsonic load that should be out sometime this year. 

Despite my enthusiasm for the 300BLK, I must admit there isn’t much real-world data regarding terminal ballistics. What is available comes from sportsmen who are using the 300BLK as a hunting cartridge and from tests in ballistic gelatin. 

These tests indicate that with the right ammo, the 300BLK can achieve 20+ inches of penetration while retaining nearly 100 percent bullet weight. Tests have also shown the 300BLK to have acceptable performance against automotive glass and sheet metal. Time will tell how the 300BLK performs on the street but the data so far is very promising. 

Easy, Inexpensive Conversion
The 300 AAC Blackout has been selling like hotcakes. The last upstart cartridge that I recall doing as well in such a short time is the .40S&W. Introduced just 20 years ago, the .40 S&W has since become a standard law enforcement handgun cartridge, combining the “stopping power” of the .45 ACP with a magazine capacity close to that of a 9mm Luger pistol. 

Unlike the .40 S&W, the 300BLK does not reduce magazine capacity of the parent firearm and a standard M16 magazine designed to hold 30 rounds of .223 Remington ammunition will accept a full thirty rounds of 300BLK. The 300BLK shares a cartridge case of the same diameter as the .223 Remington. 

This means that those looking to change calibers only need to change barrels and flash hiders. Everything else is shared with the .223 Remington, so conversion can be accomplished easily and with minimal expense. Many companies are now making complete rifles for those not interested in conversion.

Travis Haley says the 300BLK is what you get when the .223 Remington and the 7.62x39 have a baby — and he’s right. We now have a rifle that combines the accuracy and ergonomics of the M16 with the downrange punch of the AK-47.

Get ready. Interesting things are in the works!

About the author

Andrew Butts has served as a soldier in the Army National Guard and also served as a correctional officer in Montana, and is currently with a federal law enforcement agency. Butts currently holds an Expert classification in IDPA and an A classification in USPSA in both Limited and Single Stack Divisions.

Contact Andrew Butts

Join the discussion

Brand focus

Sponsored content
3 police firearms training tips for novice shooters

3 police firearms training tips for novice shooters

Police officers know that a person will never get good at any physical skill without the right training, and that includes the operation of a firearm

logo for print