If you look at the large, heavy .30 caliber Match Grade, spitzer style, low drag bullets that are often loaded into the .300 A.A.C. Blackout, they take time to "settle down" after being fired. Fired at supersonic high velocity in heavy barreled, match grade bolt actions, many of these bullets deliver smaller groups at 300 yards, than they do at 100. None of this is desirable in a short range, suppressed, rapid fire Carbine. This experiment was like trying to breed a dog with a cat. You won't get a "Dogat".