The stats were regarding homicide. Unless accidental deaths were included, training wasn’t an issue. Homicide, compadre, doesn’t happen because of a lack of training. It happens because someone decided, in their dark mind, to end another person’s life.
Oh, and 30 rounds a minute is a pretty bad benchmark; that’s a round every 2 seconds; any semiautomatic firearm can fire at least twice as fast as that without breaking a sweat. Do a little research. The biggest difference between an AR and a “normal” rifle is that one looks mean and the other doesn’t.
Last thing: if you’re going to hand a kid ANY gun without proper training first, yeah, that’s a recipe for disaster. So how does that affect homicide rates again?