First off I see nothing wrong with 40 yards after the shot scamper but I agree with the notion of dropping down from the 150's. I have long been a fan of the nosler bt, for me no other bullet has put the spins on deer like it with a rib/lung shot location. When I used a 270win 130gr BT's were my choice, not the best choice for a flush shoulder shot in tight as i found out but behind the shoulder dynamo!

Or another option is stick with 150's and try taking 1/4 away shots - punch ribs, vitals and opposite leg/shoulder. My personal favorite shot angle on any game.