They shouldn't. But you won't like what I have to say next: that's because the rational target for regulation should be any semi-automatic rifle with a detachable magazine. And (I'm relating a fact here): that's what the original proposals were. We don't ban cosmetic features because legislators are stupid; we ban them because the firearms lobby is powerful, and scrambled the original proposals.
(Again: I think another problem with firearms regulations is that they've been based on bans, when what's in fact needed is licensure --- in the US, for historical reasons, probably presumptively-issued licenses).
(Again: I think another problem with firearms regulations is that they've been based on bans, when what's in fact needed is licensure --- in the US, for historical reasons, probably presumptively-issued licenses).