Best case scenario you would have clipped a lung,but it could have went into the intestines.My friend shot one just like that,but he was going away.It did the same as yours went in about 5" and stopped.No pass through means poor/no blood trail.We found the hog the next day only 100yds away.Maybe you hit a lung.They can go a long ways on one lung though.Tell us if you find him or not.

Does this diagram help you?