It is easier if you go for the shoulder shot because you have a higher chance of killing the hog with out it running away, I usually go for a head shot though because it is a cleaner kill but it depends on how experienced and how far away you are. I have shot some big hogs from time to time, and most of them have been head shots. I use a Tikka T3 22-250, with grey tip bullets for head shooting, but if you are aiming for the lungs or heart I would recommend hollow points just to be safe.