My primary self defense weapon for the home is a shotgun.
When fired from a 20-26" barrel, the M193 5.56mm round is a superb hog killer out to 150-175 yards. After about 175 yards it quickly loses its magic.
When the hog is hit low behind the shoulder; the bullet penetrates 5-7", yaws and fragments. The bullet shreds the heart, lungs and diaphragm.
Col. Fackler is a retired Army medical doctor. Military bullet wound patterns:
http://bajaarizona.org/fklr/fklr.html