> Are gun barrels unregulated in most US states? I’ve very familiar with US firearms law, and to my knowledge no US state regulates barrels. > So no one is pr

> Are gun barrels unregulated in most US states? I’ve very familiar with US firearms law, and to my knowledge no US state regulates barrels. > So no one is printing guns in Slovakia yet (AFAIK :-)) Check out the FGC-9. The plans include instructions for creating a rifled barrel using electrochemical machining (ECM), using 3D printed tools.