The basic answer is yes, a.22lr can easily kill a hog with a brain shot. These, once again, must be head shots. You're just wasting ammunition, injuring pigs, and making them angry in the vitals. They will charge you. Hogs are very tough animals to kill. They are resistant to most poisons and have thick skin which protects them from most weapons. A knife may be able to pierce their skin but not all hogs will do so. A gun is your best bet for killing them quickly. They don't run away like chickens or ducks do when they are being hunted so it's hard to hide from one. Hogs will root out food in other people's gardens/fields/orchards so be careful where you shoot them to avoid hitting humans or livestock. You should take this opportunity to teach children about wildlife and give them a chance to experience shooting a firearm. This will help them understand why it is important to protect endangered species while giving them an opportunity to learn about guns and safety.