>>4361063 (last)
I know many will disagree, but I support this classification. A modification of the firing mechanism to allow full auto fire is also pretty simple, but it turns an AR15 into a machine gun.
A bump stock creates a sort of machine gun that's less accurate and harder to use, in other words it's even more dangerous than a purpose built machine gun. If you're going to have a full auto weapon, at least have a proper one.
Since we regulate machine guns, it makes no practical sense to leave this easy and dangerous loophole. If this classification is incorrect, the solution is to deregulate full-auto weapons in general.