Looking back over my records, since I started building and shooting longrifles about ten years ago I've killed 16 whitetails (Maryland and Iowa) and 3 sika with them loaded with roundballs. Almost every whitetail the ball was found just under the skin on the far side. None went over 80 yards (1), most fell 30-50 yards after the shot, four fell dead on the spot. Not much blood trail on any of them. Only had a problem finding one, but that doe fell and died in a marsh hole and was covered with mud and water, took a bit to figure that one out. Used .40, .45, .54 and 16 ga balls and all worked.
The key is shot placement. With an arrow I want heart/lung, becuase that kills by blood loss. With a ball or bullet I only aim heart/lung if it's a long shot for the size of the target area, anything under 50 yards I aim high shoulder with a gun. That takes out one or typically both front legs, some lung and several major arteries. Even if they don't bleed they still plow a pretty good trail to follow pushing their front end. Some meat loss, but when you hunt an area with ultra thick cover and a 30+ deer limit for the season, you want dead and dead fast.