Stopping power of the round fired and the accuracy of the gun determines it's lethality not rate of fire it doesn't matter how many shots per minute you can fire if they can't stop the target or even hit it. If you need a rounds effective stopping power, there are ballistics formulas all over the place.
???? How do you figure, since the U.S. murder rate is up from when full autos were legal and readily accessible.
No, it's not because they are illegal, because as it has been pointed out, they are legal if you meet the proper requirements. People aren't killed by full auto weapons often because the guns are easily traceable, they are expensive so it isn't a weapon you'll just ditch somewhere, the rounds get expensive after a while. A cheap .38 will kill someone just fine, and a 20$ street gun isn't going to be missed when thrown into the river.
I looked on google for a list of gun lethality rating, but I couldn't find it. That list may change my opinion on this thread.
Do you have any source for gun violence from automatic assult weapons?
I couldn't find that either.
There is a difference from murder rates from guns (because most murders are from handguns as everyone says) and murder rates from other weapons.
As I said, there is nothing you can do with preventing most killings with handguns. Groucho Marx had a very interesting point about outlawing guns that can be concealed. But that will create an even larger underground market, and not to mention that it would be harder for people to defend themeselves with guns.
Also, even if gun regulations on guns in general normally increases crime, the people who get the guns illegally need to get those guns from somewhere. Therefore, in the long run of having regulations on guns, as the ones that were purchased legally break down, then I would suspect that crimes rates would fall. That may take 50 years or much more though.