re: AR hunting rifle?

My gf and I both killed a deer with my 300 blk this year. Mine went about 20 yards and crashed, hers dropped where it stood. I shot mine at about 30 yards and she shot hers at 100 yards. It puts a hurtin on them out to 200-250 yards. I shoot a 110gr barnes tac tx, the same ones posted above on the bear but lighter. I would take my blackout over a 6.8 any day! However, if the woods I hunted weren't so thick, I would invest in the new m&p10 308 with ambi controls since I'm a lefty.