You will not be disappointed with this bullet or grain weight. Both my buddy and I shoot .300 win mags with 168 barnes tsx. We both use reloader 19. My buddy uses 77gr's of powder and my load is 78gr's. Neither of has have had our loads on a chrony yet. I shot a cow elk at about 400 yards, and it was a thru and thru, but went down right away. My buddy shot his cow at about 350 yards, and found the bullet, and he weighed it, and it weighed 167.2 grains. So I would say that is pretty good bullet retention with a perfect mushroom. We also both shot our whitetail bucks at about 300-350 yards, and both of these deer died on the spot.