Given that quite simple G-code, say a pair of nested circles with code for tool changes/accessory activation, can make two wildly different parts depending on which machine it is run on:
- a washer if run on a small machine in metric w/ flood coolant
- a lamp base if run on a larger router in Imperial w/ a tool changer
and that deriving what will be made by a given G-code file in 3D is a problem which the industry hasn't solved in decades, the solution of which would be worthy of a Turing Award _and_ a Fields Medal, I don't see this happening.
A further question, just attempting it will require collecting a set of 3D models for making firearms --- who will persuade every firearms manufacturer to submit said parts, where/how will they be stored, and how will they be secured so that they are not used/available as a resource for making firearms?
A more reasonable bit of legislation would be that persons legally barred from owning firearms are barred from owning 3D printers and CNC equipment unless there is a mechanism to submit parts to their parole officer for approval before manufacturing, since that's the only class of folks which the 2nd Amendment doesn't apply to, and a reasonable argument is:
1st Amendment + 2nd Amendment == The Right to 3D Print and Bear Arms
