In Canada, a 3D-Printed Rifle Breaks On First Firing 204
Not all 3-D printed guns can encounter the smooth, uneventful success of Cody Wilson's Liberator; Daniel_Stuckey writes with this excerpt: "A Canadian has just fired the first shot from his creation, 'The Grizzly,' an entirely 3D-printed rifle. In that single shot, CanadianGunNut (his name on the DefCad forum), or "Matthew," has advanced 3D-printed firearms to yet another level. Sort of: According to his video's description, the rifle's barrel and receiver were both damaged in that single shot."
Re:I still see a market .... (Score:4, Interesting)
If it were purely a matter of pressure, you could probably get away with expensive plastic. I wouldn't want to be the person in charge of 3d-printing such a beast; but fiber-reinforced polymers are pretty tough (even better results, and markedly higher fabrication costs, if the fiber structures are correctly oriented to ensure that pressures on the barrel are mostly applied as tensile stress on the reinforcing fibers). At that point, though, you are probably talking a production process more difficult, possibly even more expensive, than the one used to produce normal metal barrels.
Even more vexingly, you still have heat and barrel erosion to deal with. If you don't mind a smoothbore with suitably low rate of fire, that's survivable; but 'rifle' more or less requires modestly complex barrel geometry tough enough to survive having a bullet rammed through it at alarming speeds. Plus, if you are using chemical propellants, the tendency of plastics to either start breaking down, or go into glass transition and send all their structural properties screaming through the floor, at fairly low temperatures combines beautifully with their relatively low thermal conductivity....
Re:I still see a market .... (Score:4, Interesting)
But, as I understand it, nobody actually wants a 3D printed gun - they're just trying to bait the gun-grabbers into attempting to restrain free trade and stifle free speech for their agenda, to make the gun-grabbers look even worse.
And it's working quite well. Here in the United States home made firearms are mostly legal as long as you don't sell them. Mainly because it's too hard to regulate, and most of them blow up anyways. The only restriction is an old law saying guns have to be detected by metal detectors.
Now you have all these states and cities that are passing laws banning 3d printed weapons. Side note, I can't wait until someone is arrested because they used a 3d printed toy as a "weapon." Then the US said it might be an export violation and told Defense Distributed to pull all the files. Boom, instant free speech violation.
What I'm curious about is the correlation between gun-grabbers and people who want to Censor the internet. Since they both use the same language about "protecting children" or for "public safety" I imagine it's the same people. Has anyone done a study on this?
Re:I still see a market .... (Score:5, Interesting)
The cheapness of the plastic isn't really an issue - trying to pretend it has the same properties as steel is. You could make a fairly workable rifle with 3D printing but you'd have to adjust the design to match the materials used, in other words it would have to be bulky enough to make a WH40k Space Marine's double bolter look like a flimsy toy in comparison. Two to three inch thick walls on the barrel would make it a lot more durable, although melting becomes your problem then.