... just like a bunch of hicks with Kentucky rifles couldn't be of any use against the greatest military power the world had ever known to that point (1770s), with its vast navy, cannon, artillery, and mercenaries.

It's no longer the 1770's. If you wish to engage in revolution with a bunch of plastic guns and low power bullets be my guest but it's your funeral.

A Glock is also largely made of plastic, but the barrel is made out of steel. Presumably this is because they would like to be able to fire it many times and because this greatly reduces the risk of injury to the user of the gun.

It's hard to cut useful rifling into anything but metal or ceramic.

A revolution mainly just takes strength of numbers; it's different from a war. The Berlin Wall fell without a shot, for the most part. And there's an awful lot of killing going on in urban areas of Israel right now with just blades. Likewise, 9/11 was accomplished with just tiny blades.

> Likewise, 9/11 was accomplished with just tiny blades

tiny blades and the idea that you shouldn't fight back.

Could be useful for getting through metal detectors for an assassination. All you need to do is get the bullet through and you can hide that in a cap or a shoe.

I've seen that movie.

http://www.imdb.com/title/tt0107206/

I don't see how this is going to be of use for anything else than crime. It's too dangerous for home defense, but just about OK for shooting someone point-blank.

Do you really think that, even if widely available, this would be used more often for crime than for harmless purposes like simply experimenting with 3D printers?

You can experiment with 3D printers just as well by printing toys for kids or plastic roses, simple machinery and other gizmos. Once you decide to print an unlicensed, unregistered gun and get ammo you'd better be prepared to use it for something because in a large number of places you've just crossed into illegal territory which would seem to be a lot of trouble to go to just to 'experiment with 3D printers'.

I don't think that you'll get much mileage out of that line for your defense when you're caught with a stash of illegal weapons.

No, your honor, those 25 guns are misprints, really...

I'm not much of a gun enthusiast. I don't own any. But I certainly see the appeal of 3D printing a gun just to get it to work, because it's cool. The same goes for other things I think are cool, like jet engines, stirling engines, airplanes and multirotors, trebuchets, 3D models of fractals, complex gear systems, etc. I'd be interested in printing all of these things just as a hobby, and a 3D printed gun is no different. There's no reason why a gun is unique, such that I or the average 3D printer hobbyist would only be interested in printing one to commit a crime.

Small arms are used to gain large arms. That's how it always works.

If you manage to get close enough. Rifles have range, this gun does not. It will definitely kill you at close range but you're going to have to get there and you should hope your opponents are very few in number.