Re: I See It Now, U need an FFL For a Printer
There are commercially-available methods for rapid-prototyping (AKA "3D printing") of metal parts. This is currently used for things like tooling (molds) for plastic injection molding. Pretty cool stuff, and rapidly approaching the point where someone could indeed use it for low-volume production of firearms parts. I wouldn't yet be real keen on using it for a load-bearing receiver such as the typical bolt gun action, but it'd probably be workable for those firearms such as AR15s that lock the bolt into barrel extensions.