I have been looking into purchasing an upper chambered in this AR-15 platform round. Anyone have any experiences?? Does it come close to living up to the published data? I have a ton of 6.5 Grendel magazines and brass that is outside of the weight range I utilize that would work great for this. I am thinking of shooting 150g Nosler BT or Hornady SST for whitetail and smaller game inside of 300 yards. I am interested in better super sonic performance than my 300BLK chambered rifles without dragging out my heavy barreled LR-308...