Semiautomatic .22?
Well, the way in which we measure it is- I think most scholars would say- is that as long as you have a weapon sufficient to be able to provide your self-defense. I did one of these town-hall meetings on the Internet and one guy said, "Well, what happens when the end days come? What happens when there's the earthquake? I live in California, and I have to protect myself."
I said, "Well, you know, my shotgun will do better for you than your AR-15, because if you want to keep someone away from your house, just fire the shotgun through the door." Most people can handle a shotgun a hell of a lot better than they can a semiautomatic weapon in terms of both their aim and in terms of their ability to deter people coming. We can argue whether that's true or not, but it is no argument that, for example, a shotgun could do the same job of protecting you. Now, granted, you can come back and say, "Well, a machine gun could do a better job of protecting me." No one's arguing we should make machine guns legal.
If you want to protect yourself, get a double-barrelled shotgun, have the shells, a 12-gauge shotgun, and I promise you, as I told my wife- we live in an area that's wooded and somewhat secluded- I said, "If there's ever a problem, just walk out on the balcony here, walk out, take that double-barrelled shotgun and fire two blasts outside the house." I promise you, whoever's coming in, is not. You don't need an AR-15. It's harder to aim, it's harder to use, and in fact you don't need 30 rounds to protect yourself. Buy a shotgun. Buy a shotgun.