Wow...................now any criminal can buy a 3D printer, download the plans, and print their own guns, no store required.
No serial number or ballistics record either.
My understanding of this technology holds that only
some parts of a firearm can be
usefully produced via this "printing" (replicating) process while some of the more critical parts cannot. I can understand how a frame might be usefully produced, along with a stock and those mechanical parts which are not subjected to the more stressful functions of a firearm such as the breech, which will experience the full explosive force of each discharge. And I cannot understand how a rifled barrel could be "printed," i.e., composed of a material which is capable of being melted then re-solidified sufficiently to sustain the swelling stress of repetitive, transient compressions.
Those are my personal understandings and are based on my very limited knowledge of this "printing" technology. So I will be grateful for any knowledgeable corrections and education on the subject.