I do not know if this is what you are looking for, but from MY PERSONAL experience.

You shoot a hog with the 556 (fmj) in the body it will run for a while before it lays down. In fact you are better off to put two to three rounds in it if you can get them off in time. If you hit it in the head or neck it is pretty much a one shot deal though and it drops.

You shoot a hog in the body with the 308, it crawls maybe thirty to twenty yards and lays down. You hit it in the shoulder, neck, or head it drops in its tracks.

When I go hog hunting, i carry a 762x39 or 308 if I want them dead in the field. I carry my 556 if I just want alot of hits and never plan on recovering the hogs.