Andy Greenberg, of Wired, wrote an article about his experience using the Ghost Gunner CNC milling machine by Defense Distributed. Andy tried three types of AR lower gunsmithing. He started with the traditional 80% lower and tried to use a drill press. His results were unsatisfactory. Andy does admit he has very little knowledge about tools and gunsmithing.
Next Andy tried using a Makerbot to print out an AR-15 lower receiver. However according to his gunsmith consultant, the 3D printed lower would not work as a functional lower.
His final attempt was with the Defense Distributed Ghost Gunner milling machine. Of course the results were spectacular.
Throughout the video above, Andy keeps using the word “untraceable”. i don’t think it means what he thinks it means. Tracing a serial number of a gun only tracks who made it, who sold it, and who bought it. It does not act like a GPS locator or lojack. If the gun is stolen, the serial number will only tell you who was the last person to legally purchase it. Tracing the serial number does not stop a crime with said gun. The act of seizing the firearm from a criminal will potentially stop future use of that firearm in a future crime. The only benefit to tracing a serial number would be to see if the person who last bought it, might have sold it or gave it to someone who is not supposed to own a firearm and thereby committed a straw purchase. However none of that stopped the original crime from happening.