Do legislators actually have to take the step of banning bump stocks, or could the ATF (or other government agency) unilaterally state that the addition of one to a weapon means that it now has all of the attributes of a Machine Gun as defined in the National Firearms Act of 1934?
"Machine gun." (b) The term "machine gun " means any weapon which shoots, or is designed to shoot, automatically or semiautomatically, more than one shot, without manual reloading, by a single function of the trigger.
My intuition is that if the answer is "yes," then owners of bump stocks could still own them without breaking the law, they just won't ever be able to apply that accessory to their weapons without running afoul of the National Firearms Act and risking a $2,000 fine and 5 years in jail. Is this understanding of how the law works correct?