The 300 AAC Blackout, also known as the 300 BLK, is a relatively new cartridge designed for use in the AR-15 platform. Developed by Advanced Armament Corporation (AAC), the 300 BLK was specifically created to provide a more versatile and powerful alternative to the 5.56 NATO cartridge. The 300 BLK uses a .30 caliber bullet, which gives it significantly more stopping power than the 5.56 NATO while still allowing it to be used in the same magazines and firearms.

One of the key features of the 300 BLK is its versatility. It can be used for a wide range of applications, from hunting to self-defense to tactical operations. It can be fired from standard AR-15 magazines and can be used with both supersonic and subsonic ammunition, making it ideal for both short- and long-range shooting. The 300 BLK also has excellent terminal ballistics, which means that it is capable of stopping an assailant quickly and efficiently. Overall, the 300 AAC Blackout is an excellent cartridge that provides AR-15 owners with a versatile and powerful option for a wide range of shooting applications.