Print your own...

 

From the PYOR (Print Your Own Rifle) department:

 

 

http://www.thefirearmblog.com/blog/2013/05/30/warfairys-latest-additions-charon-line-printable-ar-15s/

 

They can try to ban or register 3D printed weapons. They were registering typewriters in Ceausescu's Romania...