Can’t speak to 400 yards, but I used the Speer 150 BT in my old mod70 for a little bit. The three deer I killed were all at 40 yards or less and expansion was explosive. 1 hit a rib going in and produced 4 exit wounds, 1 did not exit and produced a 4” entry wound. The third hit the neck and nearly severed the head from the body.. Safe to say they were a bit soft for that application. They were more accurate in my gun than the Sierra.
Old70
