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Comment by notepad0x90 | Hacker News Reader

is it because guns are easy to get without printing?

Because it is possible to print molds for cast iron, I wonder what else you need beyond that (although, don't indulge me if the topic is going in the illegal direction).

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not a gunsmith, but cast iron manages to be both soft and brittle at the same time. and the barrel and bearing parts would have to be machined anyways. you have to try to harden it too. its probably easier to just machine the whole thing out of decent quality steel. just guessing.

really? they didn't have machining in the 1700s. how about a good'ol musket? or a bit more modern: a gatling gun. I always thought those were made under coarse conditions. I mean, people just need something that makes a spark against gun powder,goes boom and shoots really fast projectiles. If a shotgun is possible, then an automatic shotgun doesn't feel like it's a stretch. I would think the firing mechanisms might not be tolerant of amateur techniques, but the reloading and trigger parts at least might be. I'm also not a gunsmith, no idea what I'm talking about for the record.

They certainly didn't have mills as we know them in the 1700s, but lathes, drills, and subtractive manufacturing had been in practice for millenia. You could say they were "machined by hand". Most early firearms (barring large-bore guns like cannons) were made from forged steel or iron, which is significantly stronger than cast iron due to its lower carbon content and regular grain structure. These forged parts were then worked on by gunspiths with cutters and abrasives to produce parts in tolerance for their mechanism. Cast iron (or more typically in early warfare, bronze) was suitable for cannons and large-bore guns due to the mass of the finished gun; more metal meant that the gun could withstand more shock, but even then they could fail catastrophically due to material fatigue or failure.

Well, the kind of guns politicians are afraid people will make at home are not intended for durability. But things like street crime, school shootings,etc.. where it's just a one and done affair.

Complex manufacturing of improvised firearms has been practically made obsolete by the commodification of both steel tubing and cartridges. "Pipe guns" are incredibly easy to make, and require little more than a pipe, a cap, and a drill (which can sometimes be omitted as well). Many common cartridge diameters very closely or exactly match commercially available pipe diameters, and the hardware to make a single-shot firearm is ubiquitous in any store that sells plumbing supplies. Pipe guns are simple and cheap enough to make that some people abuse gun buy-back programs by deliberately manufacturing pipe guns for pennies and pocketing the money these programs offer [0]. These are real, functional guns, and I promise they're simpler, faster, and cheaper to manufacture than any 3d printed gun.

0: https://www.thefirearmblog.com/blog/2014/11/17/handing-zip-g...

I assume this is mostly for a shotgun shell affair? otherwise the difference in bore, and particularly the seam that is present in almost all steel pipe (unless its drawn-over-mandrel which is a more speciality product), would make it pretty dodgy to fire a proper round

they also didn't have 3d printers in the 1700s, so I figure the 3d printer doesn't add much if it requires all of these post-processing steps like molding, casting, and finishing

Not cast iron

https://revolutionarywarjournal.com/how-colonial-gunsmiths-f...

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