while i can technically see where they are coming from......because if you compare the mechanial operation of a AR bolt action upper to that of a Rem 700......they are identical......and seeing as the Rem 700 action is a "firearm".....so 'in thier minds'....should be the AR upper.
HOWEVER......the bolt action AR upper is useless on its own......it CANNOT fire without the lower reciveer (which is already a firearm).....unlike the rem700.
so by that logic, ALL upper receivers are firearms semi or bolt.........which is absurd because the ATF is essentially saying AR pattern rifles are "2 firearms".