(C) a semiautomatic pistol that has an ability to accept a detachable magazine and has at least 2 of--
(i) an ammunition magazine that attaches to the pistol outside of the pistol grip;
(ii) a threaded barrel capable of accepting a barrel extender, flash suppressor, forward handgrip, or silencer;
(iii) a shroud that is attached to, or partially or completely encircles, the barrel and that permits the shooter to hold the firearm with the nontrigger hand without being burned;
(iv) a manufactured weight of 50 ounces or more when the pistol is unloaded;