[omginternets]

>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.

[LorenPechtel]

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.

[omginternets]

>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...

[jiofih]

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.