"The AR-15, the civilian version of the military assault rifle (M16 or M4), has become the most commonly used rifle in US mass shootings; the recent shootings in Parkland and Las Vegas, for instance, testify to the effectiveness of this weapon’s design. It was made for the military, to allow members of the armed forces to better dispatch multiple enemies in short order; in the hands of civilians, it not only clearly serves the same purpose for some individuals, but it’s unclear what other purpose it could serve, given how and why it was made. ...a typical 9mm handgun wound to the liver will produce a pathway of tissue destruction in the order of 1-2 inches. In comparison, an AR-15 round to the liver will literally pulverize it, much like dropping a watermelon onto concrete results in the destruction of the watermelon. Wounds like this, as one sees in school shootings like Sandy Hook and Parkland where AR-15s were used, have high fatality rates... The efficiency of the AR-15 is further compounded by large capacity ammunition magazines that permit feeding 30 or more bullets into the rifle without reloading. Mass shootings with high fatalities are fundamentally the result of the combination of a deranged individual who wants to end the lives of a large number of random humans and his or her ability to access an assault rifle."