You can make a knife from a sharpened spoon, but you can do a lot more damage, more reliably, to more people, with a real sword. For now (although not forever) you're not going to 3D print an AR-15 Lower.
It is easier and more economical to mill with a cnc. It is probably far cheaper even to just walk to the gun store and buy a rifle than it is to 3D print something similar.
A CNC is something that is pitifully easy for a regulatory agency to track, as far as large numbers of purchases go. See: that fellow who was milling AR-15 lowers and just got busted. We're talking about the difference between machining metal, and downloading and printing a schematic. I hope that you do see the difference.
It is easier to track distributing a sold product. It is very difficult to track what a person makes in the comfort of their home. I dont think the federal government keeps a registry for the purchase of milling machines.
If everyone who wants to own (to keep using this one example) an AR-15 had to buy a CNC, that would be quite the commitment. If the current model of people buying many milling machines and selling their services is the only viable way to avoid that, then you've already seen the feds start to take notice. After all, if you can get word of mouth around enough to make money, you're making enough noise to be heard.
3D printing is presumably going to become ubiquitous, and require no skill or experience to operate and maintain.
But that's the thing - with the present level of technology, you can have a device that is, essentially, pre-programmed CNC to make AR lowers (which is what Ghost Gunner is, for example) for under $300.
To make a fully functional firearm from there, you also need a complete upper - can be had for another $400 or so these days; and a complete lower part kit with buffer tube and stock - can be had for less than $100. For a total of $800, some assembly required (or you can pay another $50 and have pretty much any gunsmith put it together for you).
So basically, a person can take GG and produce an unregistered, untraceable, no-background-check-required AR with it for $800-900. For comparison, the Bushmaster AR that was used in Sandy Hook shooting costs ~$700.
The cost argument is sound, and I'm not disputing it, but rather I'm thinking in the broader terms of the "Gun Control" debate. At some point in the future, maybe a decade, maybe two, supply-side gun control is going to be a pointless exercise. My argument however, is that the time has not yet come, although it's clearly on the horizon.
For now "Just get a CNC mill and learn how to use it" is still a substantial hurdle. I think it's fair to say that it's a hurdle that Adam Lanza wouldn't have managed to overcome.
You can start with an 80% lower and a $20 router from Harbor Freight and get something pretty good depending on how you set up a jig. It ain't rocket science.
No it isn't, but look at the instructions on a pack of ketchup some time and bask in the glory of the LCD. "Set up a jig" is alien babble to a huge number of people, for whom, "Press print" would not be.
Heh... sure. That, and blowing yourself up because the Navy Seal teaching you to make C4 was actually a 14 year old. The internet is a very YMMV experience, often that variance has to do with what you put into it. If the only people who can overcome a law are those smart and resourceful enough to learn how to mill their own guns, yet still criminally inclined, I'd say you've minimized your problem nicely.
this has already been done plenty of times, and i have a sneaking suspicion is far more widespread than anyone is letting on.
meanwhile, you can just buy a hundred 80% lowers off the internet for probably less than a grand, and keep them around just in case.
plenty of "normal" people stockpile this stuff. they just aren't telling anyone about it.