Look at Di-Fi's list of "assault rifles"  They got to it by leafing through a gun catalog and anything that "looked menacing" was added to the list.  Most were semi-autos.  The apparent idea was to ban ALL semi-autos through this slight-of-hand and then once 2/3 of the arms were banned, picking off the rest should be easy targets.  How about a 22LR assault rifle?  Speaking of targets...