I personally own a gun that uses .22 for home safety because it doesn't have the kickback of other guns. If someone is busting into your home in the night, you probably aren't too prepared anyway (unless you work at night or are a light sleeper. I'm not). I've never had to worry about a human home invader (and god willing I never will) but with good aim a .22 should be all you need to incapacitate them. The ammo being pretty dang common is also a great boon for target practice.