Take a look at these videos and tell me if this "rifle (AR-15, used in Newton)" and an improvised Glock, a handgun, are automatic weapons or not. Both have been used many times in killings.
The first one shows how easy it is to "bump" fire the Bushmaster AR-15 rifle, one of the weapons used at the Newtown shooting. Look at this video and tell me this semi-automatic is not easily converted to an automatic weapon.
A semi-automatic Glock was also used at Newtown. This handgun can also be "bump" fired. Look at this video.
That's why I'm including automatic weapons, as being used in crimes. They are military weapons designed to kill many people as quickly as possible. And why does any civilian need an automatic weapon unless he/she plans to use it to kill people? And handguns are, as I said, designed to kill people.
Hunting rifles, without large volume clips and shotguns should be enough to protect someone's home, hunt and do recreational target shooting.