300aacblackoutcom – “At 300 meters, 300 BLK has 16.7% more energy than 7.62x39mm. Max effective range, using M4 military standards for hit probability, is 440 meters for a 9 inch barrel, and 460 meters for a 16 inch barrel. 300 BLK from a 9 inch barrel has the same energy at the muzzle as a 14.5 inch barrel M4, and about 5% more energy at 440 meters – even though the barrel is much shorter.”