My philosophy is by using too small of a bullet you are limiting your shots. Sure if you can catch one feeding a side of the head shot is practical. But many/most of my shots are passing shots and a headshot may be doable but IMO unreliable. Body shots on a moving Hog are hard enough.
Germans have been hunting Hogs for centuries (more like Millenium) and their philosophy is bigger is better. A Hogs skin closes quick after being punctured, which makes sense, much of their life is spent running through thickets at night, punctures are common. If a Hog doesn't fall quickly, the blood trail is likely to disappear quickly. The German philosophy is the bigger the hole, the more likely you are to recover the Hog.