The proportion of such weapons on the street is on the order of a rounding error.

Yeah, 3d-printed guns are essentially nonexistent in criminal hands today. (to the best of my knowledge)

Sure, but the evidence from other countries strongly suggests that this would change if commercially made guns got harder to obtain.

In the UK and Europe, criminals modifying replicas or other close starting points is quite common.

Source for that Europe claim? That’s what we call a stretch. A earth-to-moon kind of stretch. In most of Western Europe gun crime is basically non-existent outside of turf wars, drug rings and bank robberies. Your odds of being killed or robbed at gunpoint are close to zero.

You know where modifying guns with 3D printed parts is common? The USA, since you can turn many of the commercially available ones into automatic weapons.

>You know where modifying guns with 3D printed parts is common? The USA, since you can turn many of the commercially available ones into automatic weapons.

People have done it, but it is not common at all.

Moreover, for the time being, 3D printed gun parts have an extremely short lifespan.

3D printed parts *using home printers* have an extremely short lifespan because of the materials used. 3D printers exist that can do a far better job but they're not down to the home market level yet. The "threat" from printed guns is not their prevalence but their ability to slip through metal detectors.

The real threat is ghost guns. It *used* to take a skilled machinist to make gun parts, but CNC machines at the home workshop level are now capable of doing it. Any reasonably competent adult can do it, you don't need to be a machinist.

>3D printed parts using home printers have an extremely short lifespan because of the materials used.

Yes, those are even shorter, but even industrial 3D printers are ill-equipped to print anything other than the gun's frame. Even lower receivers are a problem.

The bolt carrier group on a long-gun does not fare well unless it is made of metal (or special ceramics, in some niche cases). Same goes for the gas-block on gas-operated guns (like AR-15s or AKs), or the lever on lever-delayed blowback systems (e.g. the LAI on the FAMAS), or the rollers on something like an MP5. The DIAS required to convert an AR-15 into a full rock-'n-roll model has to bear a lot of mechanical and thermal force as well, and the 3D printed ones are notoriously unreliable. They can chip, deform, or fray at the worst possible time, releasing the hammer. They can fail to retain the hammer, and neuter your weapon in a gunfight. Most importantly: they always do this. The good ones can barely get 100 rounds off.

Handguns and long-guns likewise need hard, heat-resistant materials for firing pins, ejectors, chambers and barrels. That's unlikely to change anytime soon, unless we suddenly discover new polymers with hardness and thermal properties on par with steel.

And here's the dirty secret: you can already buy plastic guns. They're called Glocks.

>The real threat is ghost guns. It used to take a skilled machinist to make gun parts, but CNC machines at the home workshop level are now capable of doing it. Any reasonably competent adult can do it, you don't need to be a machinist.

Any reasonably competent adult can buy an 80% lower receiver [0] and produce a fully-functioning AR-15 lower receiver with a hand-held file and a few hours of work. And this is legal. The rest can be legally purchased without any oversight, because the lower receiver is the only thing that qualifies as a gun.

3D-printed "ghost guns" are a myth invented by TV talking-heads to scare pearl-clutching soccer-moms in the 80's. The reason they are a myth is because it's cheaper, safer and easier to just build a real, usable gun that wont melt in your hands. And again: this is doable with polymer parts, too.

To reiterate, because it bears repeating: the world you fear has existed for at least 25 years.

[0] https://www.5dtactical.com/ar-15-80-lower-receivers-s/109.ht...

This was in response to laverya’s comment above. I agree that 3D printed guns are still a fantasy problem, that’s the point I was making.

There was a terrorist in Germany that built a whole arsenal of home made weapons. He tried to storm a synagogue but since he couldn't get access to real gun powder he had to get a substitute. Subsequently he failed to bust the door open and just shot a white passerby and then he went to a kebab shop to shoot the clerk. Considering his goal was to kill 30+ jews this is a pretty good example how gun control saves lives.

> he failed to bust the door open and just shot a white passerby

> a pretty good example how gun control saves lives.

It sounds like the door saved lives. He was still able to shoot people. It doesn't sound like gun control laws saved any lives; maybe the building codes did.

I think the point is that he failed to bust the door open because the makeshift gun was not powerful enough.

Did he think he could get through the door with a regular gun? Hollywood portrayals of shooting locks isn't reality.

Personally, I'd also put that down as an example of how a fixation on guns leads to failure. A truck attack or bomb might have been far more devastating.

Especially since it sounds like his substitute gunpowder worked.

Seconded. Against these idiots I think if anything guns are a safety measure. Using a large vehicle (rent a moving truck, load it with something like concrete blocks from your local hardware) and ram is actually more deadly than most mass shootings. Guns only have an advantage if you seek specific targets rather than simply a death toll.

Uh.. that’s very interesting but doesn’t seem relevant to the conversation at all.