Does this mean that either STEn part separately is NOT considered a receiver? e.g. two parts = receiver, one part = uncontrolled hunk of metal? If so then an uncontrolled (and un-serialized) tube can still go bang.
Did they happen to mention/change anything about a deactivated Sterling? If the mag housing (with serial number normally permantly brazed to the tube) is removed but otherwise intact, is the mag housing considered a receiver? or because the tube "assembly" with all the brazed bits is no longer intact, it is not considered a receiver anymore?