Here’s an exclusive story you’ll only see on TTAG: Advanced Armament Corp. will be producing their own .300 AAC Blackout upper receivers for the AR-15 platform with 12 inch barrels. They’ve previously announced shorter and longer barrels, but this is the first time they let slip this specific model. There’s been some demand for a 12 inch barrel, and we can safely say that the demand will shortly be met. No idea on time frame as of yet, but we do know one thing for sure: they’re pretty. We’ve got some exclusive video of it in action too, just click the video up top. Also look for our review of 300 AAC Blackout sometime this week for more information.