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> Domestic or hobbyist 3d printing is not going to produce a particularly strong gun, it's most likely going to only work once or twice before it blows itself apart. There is a good chance the person using it will significantly hurt themselves.

While this is true for 100% printed guns, most fosscad folks will have core components that are metal. Barrels, firing pins, etc will be metal in most designs.

Some folks claim their guns can shoot thousands of rounds with no issue.

> They will have very poor accuracy, it won't be possible to rifle the barrel on a 3d printed gun in a way that will spin the projectile.

Folks literally etch their gun barrels with the same specs as commercially available barrels. Here is one such example from the /r/fosscad community: https://www.reddit.com/gallery/106u7au

While the fear is mostly media driven, the stuff folks are making now is a little alarming. Claymores, grenade launchers, etc. If you are interested in learning about this community, check out /r/fosscad on reddit.

> Some folks claim their guns can shoot thousands of rounds with no issue.

For context, I have an AR with a printed lower that I've put ~1k rounds through without issue. In the US that's the only serialized part, and therefore the only part that would be typically purchased from a dealer and able to be "traced".

> Folks literally etch their gun barrels with the same specs as commercially available barrels.

I've made a couple of pistol barrels with ECM, and they're no less accurate than commercial stuff.

It might be interesting to know that I made those specifically in order to comply with US law - not to "evade" it. Even a single-shot rimfire pistol falls under the National Firearms Act unless it has a rifled barrel. It would have been much simpler to just use a metal tube, but I didn't want to deal with filing the forms, paying the tax, and waiting months for approval before putting together a random project that I started on a whim.

Every one of your points is extremely wrong, except the first. We don't live in 2014, and we aren't talking about the Liberator anymore. Electrochemical machining means that anyone can rifle a barrel in their closet, there are tons of designs that are fully DIY without any metalworking capabilities. The glass filled nylon polymers people are using now are equivalent to many of the polymers used in industry. The last moat truly is ammunition and frankly that is a matter of time.

> anyone can rifle a barrel in their closet

That's a bit of a stretch. I think you and a lot of other people underestimate how expensive it is. The people actually doing this are doing it just because they can. Still easier, faster and cheaper to buy a ghost gun in a state with more lax rules.

A hydraulic piston, which can be a hand powered jack, and a rifling button makes it possible to easily rifle most any metal pipe.

Plus in 99% of shootings the targets are fairly short range where rifling isnt even very important.

> A hydraulic piston, which can be a hand powered jack, and a rifling button makes it possible to easily rifle most any metal pipe.

That's not my experience at all.

You have to have a means of rotating the button rifling tool consistently as it is pulled through the bore - for an m1911, probably the most common .45 ACP pistol, that's 1 revolution per 16" of barrel.

Because it will take multiple passes to cut the rifling, you'll also need a way to index the tool for each pass.

> Plus in 99% of shootings the targets are fairly short range where rifling isnt even very important.

If you're making a gun to shoot someone, that makes sense. The far more typical case is that you're making it because you are interested in making a gun, and rifling is a requirement in the US to comply with federal law for a pistol[1].

1: The term "pistol" is legislatively defined, but broadly speaking it's anything designed to be fired with one hand and <26" in overall length.

Unless you're going for sniper level accuracy a barrel can be rifled with just the button because the die will cause its own rotation as you push it down the barrel, this is because of the trailing part of the button.

The reason rifling machines do it is to ensure minimal wear on the die, and for speed of operation but that's an optimization more than a requirement. This is also the reason why the cutters on a typical button are as long as they are: to ensure that it rotates.

You also don't need to index it for the same reason: the tool will seek the grooves made by the previous pass (except for point cutters).

It's basically just a very coarse inside thread cutter, where the thread is so steep that it will drive the tool to rotate much as the bullet will rotate when passing through. This will work with any thread that is more than 1:1.

Imagine the possibilities once we advance the state of the art in biological weapon prototyping.

What you are saying is mostly irrelevant. Access to ammunition is usually easier and cheaper, even illegally. Modern designs for 3D printed guns can be quite powerful and a lot more capable than what you seem to be assuming. Quite a few designs contain a metal barrel which isn't regulated.

There aren't that many "somewhat competent" DIYers with appropriate milling equipment and skills. It's a lot easier to 3D print a design than use manual tools to precisely manufacture something. Making it easier to kill people usually means more people get killed. A basic observation in criminology.

Obviously 3D printed guns are getting produced and are being used in crimes. The article also says that Canada has a bigger problem with guns smuggled from the US.

> There aren't that many "somewhat competent" DIYers with appropriate milling equipment and skills

A gun is a tube and a pin. No milling is required.

That would be a much less useful gun than a lot of the modern 3d-printed designs. You'd want some kind of a handle and some way of injecting the pin into the bullet and some kind of a breach (informally speaking). Now we are talking some manufacturing, be it milling or drilling or sawing or whatever. If the result supposed to be as small and convenient as some 3D printed designs are, some metalworking or very precise woodworking is required.

The article is about Canada. And apparently there is a niche for some people who'd rather produce and sell 3D printed guns than "tubes and pins". And I pointed out some of the reasons. A 3D printer reliably produces parts that are quite precise with a lot less effort. That is worth a lot of tradeoffs, even if traditional craftspeople scoff at the properties of the plastic.

On HN there will always be people nitpicking on every detail left out...

Not trying to nit pick. I'm just fairly confident there are more people that could rig up a home made shot gun than 3d print a gun.

See "ButWhatAboutAmmo" by IvanTheTroll et al. Places where people are well enough off to afford 3d printers haev already found ways around the ammo issue.

>it's most likely going to only work once or twice before it blows itself apar

LMAO see FGC-9.

>it won't be possible to rifle the barrel on a 3d printed gun in a way that will spin the projectile.

But it is possible to 3d print a mandrel for ECM machining, in a way that basically anyone can easily rifle for very low cost. See ECM machining guide as part of FGC-9 build. This sounds complicated but in practice very simple, print the part and attach a pipe along with pumped water/electricity and you get very nice accurate rifling tested to perform about as well as glock oem barrel.

>It would probably be better than a 3d printed one too.

Not typically at least using the most popular expedient arms manuals. The magazine and feeding typically performs much poorer than say modern 3d printed like FGC-9. Repeatable in-tolerance magazines/feeding have always been the weak point of most home machine shop made stuff and 3d printing has mostly solved that problem.

These points, while good, apply mainly to those with regard for the law.

The scofflaws that are the main threat shall doubtless have other arrangements.

While some of your assertions were true in the past, most are no longer so.