I understand the intent, but feel that there are so many other loopholes that put much worse weapons on the street than a printer. Besides, my prints can barely sustain normal use, much less a bullet being fired from them. I would think that this is more of a risk to the person holding the gun than who it’s pointing at.
Yeah, a 3/4 inch pipe will fit a 12 gauge shell pretty well, and some pipes will stand a lot of psi.