The problems mentioned sound like placement was bad. Your indifference in tracking wounded game leads me to belive you have other careless habits also. Did you bench and sight with those new bullets before hunting?
I use Nosler BTs in my 30-06. Their expansion and retention have been perfect at ranges from 5 yards to much longer ranges. Deer dropped where they stood and there was minimal meat loss. My experience indicates, to me, they BTs are basically Partitions with plastic tips.