(Retired airline pilot) Bill Cooper may know how to fly, but not much about weapons.
1. Ownership of full automatic weapons is not allowed by civilians in the U.S.
2. Semi- or single-shot-per-trigger-pull weapons are legal. This includes rifles, shotguns and pistols.
3. “Military Style” is only in the opinion of an individual. Just because it LOOKS military does not make it more dangerous that one that does not.
Retired Tactical Air Command fighter and airline pilot