is there a difference between 300 blackout and 300 aac blackout
The .300 AAC Blackout (designated as the 300 BLK by the SAAMI and 300 AAC Blackout by the C.I.P.), also known as 7.62×35mm is a carbine cartridge developed in the United States by Advanced Armament Corporation (AAC) for use in the M4 carbine. Its purpose is to achieve ballistics similar to the 7.62×39mm Soviet cartridge in an AR-15 while using standard AR-15 magazines at their normal capacity. It can be seen as a SAAMI-certified copy of J.D. Jones' wildcat .300 Whisper. Care should be taken not to use 300 BLK ammunition in a rifle chambered for 7.62×40mm Wilson Tactical.
.300 AAC Blackout