I have a registered, pre-86 AR-15 drop-in auto sear. Can I assemble a new rifle in “assault weapon” configuration (flash suppressor, bayonet lug, collapsible stock) using this sear?
Yes. When the auto sear is installed, not only is your firearm not a semiautomatic rifle; legally speaking, it’s not a rifle at all! Therefore, it doesn’t fall under the provisions of the ban. Beware, though, that if you ever take the auto sear out of the receiver, you will be left with an illegal “assault weapon.