Most "hunting rifles and handguns" are automatic, Semiautomatic namely. You cannot purchase, at least with any sort of ease or reasonable price, a fully automatic weapon in America.
The AR 15 is generally chambered in 556/223, a considerably smaller round than the 308 that is common for hunting. Lever action cowboy style guns also often use much more substantial ammunition like 357, 45LC, and the alike.
High rate of fire can be achieved with any non single shot/break action firearm, and moreso high rate of fire means nothing without the training and physical strength to control the weapon and stay on target.
People who wish to inflict mass casualties will continue to use explosives, fire, edged weapons, and illegally procured/manufactured firearms, even after a nanny state does everything in it's tyrannical power to prevent law abiding citizens from accessing such.
~66% of annual "gun deaths" are suicides, of which the seriously depressed will merely take other instantaneous avenues of self destruction such as heights or vehicles. Of the remaining third, a small fraction are either lawful use of deadly force by law enforcement or civilians, and accidental firearm deaths. Of the less than 1/3rd that are homicides, there are a few factors worth considering. These homicides take place primarily in urban centers (mostly Democrat ran ones with restrictive gun laws like LA, Chicago, Detroit, and Philidelphia), they are majorly young, black males killing other young, black males, and the most common type of weapon used are illegally acquired semiautomatic handguns. The image of the AR15 as some omnipresent baby killer is a fabrication of the highest order.
Beyond all of the above, four simple words sum up why your proposal is absurd. SHALL NOT BE INFRINGED