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."
I still see a market .... (Score:5, Funny)
ACME firearms, supplying evil coyotes for decades
Re:I still see a market .... (Score:5, Informative)
Heh - what else did they expect? Rifles keep pressure for longer periods of time (as the bullet travels down the longer barrel), increasing the chance for materials failure. Cheap plastic is not an option here, campers.
7,000+ psi for a .22LR is nothing to screw around with for the relatively sustained period of time the bullet travels down the barrel (let alone the 65,000+ psi you can generate in, oh, a .338 Win Mag.)
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Re:I still see a market .... (Score:5, Insightful)
That's the thing - I doubt there's a 3D-printable plastic out there now which could last for one rifle shot, at least outside of sheer luck.
The length of the rifle barrel is what'll kill it. A pistol dumps its internal pressures quickly - the short muzzle doesn't have to hold the pressure for more than a millisecond or two at most. A rifle on the other hand? The longer the barrel, the longer that period of time which the barrel has to hold the higher pressures. Most rifle cartridges also contain a slower-burning powder (to keep pressures at least somewhat constant as the bullet travels down the barrel), which only exacerbates things from a design perspective.
From an industrial perspective, any plastic barrel that doesn't hold up to insane tolerances (at least 3x max pressure) and do so for a very long time? Begging for a lawsuit that'll bankrupt your company, guaranteed. Also, there's no real economic incentive to make plastic barrels commercially - steel is way cheaper to acquire, machine, and temper. Now there are some specialized and niche applications (spies, special ops/forces, whatever), but they don't justify the costs.
Hobbyists OTOH don't have that kind of pressure or limitation - they're just doing it because they can.
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You are looking at what is going on now, not what will happen in a few maybe 5 or 10 years.
3D printers currently exists for wood, carbon fiber, ceramic, bronze, steel, iron, cellulose and human tissue and prices of these devices will keep dropping like what we are used to from Moore's law.
Forget these pee shooters, expect change.
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.
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The length of the rifle barrel is what'll kill it. A pistol dumps its internal pressures quickly - the short muzzle doesn't have to hold the pressure for more than a millisecond or two at most. A rifle on the other hand? The longer the barrel, the longer that period of time which the barrel has to hold the higher pressures. Most rifle cartridges also contain a slower-burning powder (to keep pressures at least somewhat constant as the bullet travels down the barrel), which only exacerbates things from a design perspective.
I think the duration of the high pressures is a second-order issue, behind the fact that most rifle rounds generate much higher pressures, period. A few examples:
Handgun rounds:
.380 ACP: 21,500 PSI
.357 magnum: 35,000 PSI
.40: 35,000 PSI
.45 ACP: 21,000 PSI
9mm: 34,800 PSI
Rifle rounds:
5.56mm: 62,366 PSI
.270: 65,000 PSI
.308: 62,000 PSI
.30-05: 60,200 PSI
I'm not aware of a single handgun round that is designed for more than 40,000 PSI, while most modern rifle rounds are in the 60,000+ PSI range. The
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You can also 3D print metal, it's a slightly different process, but nevertheless, there are metal 3D printers out there.
And if you look at the pains that the gun foundries go through to get _exactly_ the right metal properties for their gun barrels, you'd be leery of ever firing a 3D-printed gun (in 2013).
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 gu
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?
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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
That is certainly not why they're legal.
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At the very, VERY least you would use a prefab metal pipe for the barrel, if you goal were really just to make a gun. (Even a prefab plastic pipe would make a better barrel than a printed plastic barrel.)
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Most people only fire their gun about 100 times - ammo is expensive, and people have better things to do with their time. 30 shots per rifle, especially if you can print it at home, is an acceptable amount. You don't buy a $4 disposable camera and expect to win a photography contest.
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"Most people only fire their gun about 100 times"
Maybe an absolute novice with only a passing interest in firearms. I consider myself a low level gun enthusiast and I just fired probably close to 100 rounds TODAY (a mixture of 7.62x51 and 22lr) "plinking", and watched another person go through dialing in a new scope fire at least 150 rounds. Now all of these guns were semi-auto clip fed, which tends to encourage a bit of excessive/unproductive firing. But even shooting a lever action Winchester I'll usual
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....
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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.
One could imagine a polymer mixture that would contain chemicals that would cross-link randomly (or even preferentially), and at certain ratios form long chains, which would act as reinforcing fibers.
The orientation would be random unless possibly cured in a magnetic field with the right chemical components, but even randomly oriented reinforcem
Proir art deco (Score:2)
Bakelite and other thermosetting phenolic resins called from the 1920s and before called and would like their prior art back.
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There are several commercial .22 LR carbines with nylon or other non-metal barrels. Aside from being light weight, some have some interesting properties, like being either straight or broken but never bent.
I doubt it would be hard to build a receiver massive enough to handle .22 LR pressures.
But I doubt you could get a printed barrel that could handle the corrosive effects for more than a couple of rounds. The nylon barrels do it somehow, but I believe it took some fancy chemical research to come up wit
Re:I still see a market .... (Score:4, Informative)
I was wrong, parent post is right. I just learned that the .22 "survival" carbine I had been thinking of has a steel barrel; the receiver and stock are nylon.
When I lived in more open country, I used to hunt with a .30-06 slide action and 2-7x scope. Now my hunting is in brushy country where shots over 100 yards are very rare, so I use a .30-30 lever action carbine with peep sights. I've never been in a situation where a .22 rifle would be of any use, so I never looked into that caliber.
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What are you hunting? I've always taken squirrel and rabbit with .22 LR.
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.22LR is a varmint caliber. It's actually illegal to hunt anything bigger than a rabbit with it most places
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You would have to find a way for the reinforcing fiber to follow the lands and grooves of the rifling. The jacket drag causes visible twisting ( with slow motion cameras ) of lighter steel barrels simply from the bullet having a proper fit while in travel.
Unless they come up with a plastic that can be printed out easily and then work hardened ( through firing ) to a specific point I don't think they will have much luck with 3D printed rifles.
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I'd be amazed to see somebody print such a beast; but (if one simply had to prove that a rifled polymer barrel could be constructed) getting the fiber reinforcements in a polymer structure to follow the rifling might actually be doable.
For textile purposes (socks, shoelaces, ropes, pantihose, that sort of thing) circular weaving machines, capable of pumping out seamless woven tubes, of varying complexity, are ancient. More recently, with the enthusiasm for carbon fiber composites, there has been some work a
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You make some valid points.
For the purposes of demonstrating the possibilities, the same gun should be printed again, with the barrel cut down to 6 inches and the powder load reduced by firing .22 short ammunition. Such a gun would survive a couple of firings, probably. Probably literally burning out the bore would be its demise.
I doubt if any printed gun could ever last for more than a few rounds before its barrel was shot out so bad that the bullet would fall out the end. The muzzle blast might be impr
For a spy all you need is 1 shot (Score:2)
For a spy all you need is 1 shot
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With a .22 LR rimfilre, it had better be an extremely accurate shot if you intend to kill anything bigger than a rabbit with it.
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Not true at all. My father grew up on a subsistence farm. He'd hunt elk with a .22lr or sometimes a bow. He brought down many elk with that .22
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But it takes a very good shot, from a position most people would rather not be in.
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and many animals have been maimed and suffered for a long time because of stupid hunters using inadequate round for the game they're hunting. Sure a 22 LR in head or other vital area *might* kill human or deer or larger animal, but it also might not.
It is ILLEGAL in Alaska to hunt deer or any larger game with a 22 LR, for the reason I just gave. All rimfiire ammunition, which includes 22LR, is illegal for that. Illegal in my state of Illinois too and most (maybe all?) states.
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It somewhat legal in Alaska. The Alaska hunting regs specifically say you can take caribou from a boat using a .22 rimfire in certain districts.
Page 21 I think.
http://www.adfg.alaska.gov/static/regulations/wildliferegulations/pdfs/general.pdf [alaska.gov]
In Ohio, guns other then certain handguns and shotguns are illegal to hunt with during deer season except muzzle loaders of a certain type or larger. (actually, I think it's a period of months- after a certain date they aren't allowed unless that just happens to be how
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many animals have been maimed and suffered for a long time because of stupid hunters using inadequate round for the game they're hunting.
That's how humans hunted for all of prehistory. Minor wound, then track the animal for miles until it bleeds out or exhausts itself.
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many animals have been maimed and suffered for a long time because of stupid hunters using inadequate round for the game they're hunting.
That's how humans hunted for all of prehistory. Minor wound, then track the animal for miles until it bleeds out or exhausts itself.
you can just track without wounding too. some tribes in africa use that.. humans have surprisingly good tenacity compared to antelopes.
but still, it's risky, the crazed animal might run into a freeway or whatever - of course you can take down a big thing with a 22lr if you happen to hit the right spot, it's more probable that you will not though.
good luck doing that shot with something shot out of a thing with plastic rifling...
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But nobody hunts from a helicopter with a
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"Helicopter hog hunting is perfectly legal in Texas. Wild hog populations have gotten extremely out of control."
Sure, I don't doubt there are legitimate exceptions. I just meant the sort of wolf and elk hunting and the like that we've seen in films.
But if you're NOT talking about serious and harmful overpopulation and things of that nature, I put helicopter hunting right up there with clubbing baby seals.
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But ... but ... 2nd amendment...
That's what you get with the democrats in the white house!
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Not nearly as much as the pilot I imagine :-)
Re:For a spy all you need is 1 shot (Score:4, Informative)
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"Quite wrong. the .22 Long Rifle with hollow point, frangible, high velocity AND subsonic loads are all favored by assassins."
More people in non-military situations are killed by .22 caliber rounds than any other.
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bullshit. in USA, larger calibers are more frequently used, look it up.
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I didn't say
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No, that's not true either. either of the .355 (9mm ) and .357" diameter bullet (.38 special and .357 magnum) is used more often the .22 LR in the USA.
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"No, that's not true either. either of the .355 (9mm ) and .357" diameter bullet (.38 special and .357 magnum) is used more often the .22 LR in the USA."
Used for what? See, everybody here is getting their figures all jumbled up.
.22 vs. everything else.
First, I didn't say just U.S.
Second, again, I was referring to particular calibers, not
Third, I didn't say "used in crime" (which is what just about everybody is citing). I said "killed people".
Fourth, even those U.S. figures are woefully inconclusive. Most sources will give you figures that came from a single survey of Philadelphia crime (not killings) in 1985. There is another report from Philly
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but armed robber or assassin doesn't need 500 round box, does he? and how many shots fired during a crime? a $13 25-round box of cheapest 9mm or 38 special goes a long way. as for revolver, cheap ass CC Blazer can be had for $18 a box.
I've been in plenty of "1800" matches (90 rounds rimfire, 90 rounds centerfire)....truthfully the weight of the guns more than anything is what makes my hand tired.
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No, false. And citing Hollywood movies doesn't bolster the case. Most successful assassinations are carried out by heavier and/or higher velocity rounds.
22 LR *might* kill someone (sometimes a day later, as a relative of mine died), or not.
For example, some Navy SEALS were issued sound suppressed 22LR pistols, for killing patrol DOGS. They have heavier ammo for people.
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For a spy all you need is 1 shot
If you are planning to do something wildly illicit and clandestine, you might have better luck with (depending on whether you need Absolutely No Metal/searches at the entrance resistance or plausible deniability) either the cheapest, nastiest, most ridiculously common on the civilian grey market, gun in that jurisdiction, which is blatantly obvious; but indistinguishable from the background gun violence of the area or some much lower pressure pneumatic dart system with a chemical payload (Georgi Markov styl
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I was pondering the same, though my logic was "I only need 1 shot. After that, I'll have a real rifle".
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All the riffles and barrels would be identical so all you would have to do is sight them in and change the barrel design slightly or even the sights a bit to compensate in future models.
In manufacturing a regular metal barrel, the process allows near identical or similar results but not always the same. This minute diversion is eliminated with the precision of printing a barrel. Also, the point of sight attachments in regular firearms have some play as well. This is also eliminated with printing for the mos
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In Canada? (Score:5, Funny)
What happens if you try it somewhere else?
Re:In Canada? (Score:4, Funny)
What happens if you try it somewhere else?
It won't apologize so much when it fails.
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It's been proven to last up to three shots in europe, and about twenty is asia.
Big surprise (Score:5, Informative)
Rifle cartridges tend to have quite a bit more power than pistol cartridges.
Chamber pressure:
.45 ACP maximum pressure 140 MPa / 21,000 psi
Rifle: 7.62x51mm maximum pressure 415 MPa / 60,191 psi
Rifle: 5.56x54mm maximum pressure 430 MPa / 62,366 psi
Pistol:
Pistol: 9x19mm maximum pressure 235 MPa / 34,084 psi
Pistol: 9x17mm maximum pressure 148 MPa / 21,500 psi
IIRC, the 9x17mm (.380) was used in some earlier 3D printed pistol tests with limited success.
Most people receiving medical treatment after being shot by a pistol will live. Mortality is much higher for those shot by a rifle.
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Pistols are usually designed to stop an assailant rather than outright kill someone.
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But note even those pistol pressure are too huge for any plastic, even a wimpy .380 ACP (9mm Kurtz) is 21,500 CPU (roughly same as PSI)
if you value your life or use of your hand, don't use a 3D printed barrel/chamber unless there is some kind of materials breakthrough that give plastic the strength of iron.
steel is used for a reason.....
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One way to think about it (Score:2)
A 5.56mm, rifle round is much smaller than a 9mm pistol round, as the number would imply. About 3.5mm less diameter. It is also lighter, of course. However the case for a 5.56 round is as big around as a 9mm case, it is just necked down at the very end to hold the bullet. It is also much longer, as the second number implies (that is cartridge length). It is over twice as long, 45mm (5.56x45mm is the spec). So what fills that extra space? More propellant. The reason for the large case, small bullet, is to ha
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IIRC, the 9x17mm (.380) was used in some earlier 3D printed pistol tests with limited success.
I'd say with good success, rather than "limited" success.
Also, it occurs to me that if you'd like a more powerful plastic gun, you should perhaps consider the .45 ACP, which has max pressures slightly lower than the .380. Even better might be a .44 special, which has max pressures of around 14,000 PSI.
Yet another low caliber 3D printed firearm (Score:2)
Except this one is only able to fire one shot. Call me back when they can fire multiple shows using an actual "rifle" round like .308 Winchester.
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Multiple shows? Isn't one session at the movies enough?
You have the right to shout "fire" in a crowed theatre.
Too soon?
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There is a HUGE difference between a 22LR and a 5.56 or 223. Even if they are the "same calibur".
22LR, 36-40 grain, just over 1,000 ft/s
223 56 grain, just over 3000 ft/s
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Please tell me you're not that stupid? 22LR is equal to a .223? Caliber is the _only_ thing they share.
why gun powder? (Score:3)
I keep wondering why all these guys keep trying to produce a gunpowder based gun. There are some incredible air rifles out there now... .50cal, 1000fps awesome guns. Why not try an air rifle and avoid all issues involved with powder?
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They are baiting the ATF.
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So make everything but the tank on the printer.
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Obvious conclusions (Score:2)
My father once carved a longbow out of a large piece of cedar. It looked magnificent, exactly how a longbow should look. He carefully strung it, notched an arrow, and drew it back. It snapped in half. I thus concluded that a longbow will never work and it's pointless to ever use one. I'm assuming that's the same conclusion we should make from this article. I'm glad this random Canadian could save us all so much time.
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Making a zip gun out of black pipe gets ignored or you get arrested.
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One difference, those with gunsmithing skills will tell you plastic is an inappropriate material to make firearm chambers and barrels.
Cedar is an appropriate material; your father just lacked some very basic knowledge - which he can now get the internet if he still is alive and still is interested.
When will this sillieness end? (Score:4, Insightful)
Anybody with the right knowledge and some basic tools has been able to make a gun for a long time
Convicts do it in prison
People in underdeveloped countries do it using the most crude equipment imaginable
3D printing a gun, in plastic, is nothing more than an attention grabbing headline
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There is a big difference. Almost nobody knows how to make a gun. Put all the professional gunsmiths and all the amateur gun-makers that you mention together and they make a tiny fraction of 1% of the population.
With 3D printing, everybody knows how to make a gun. Download the plan, load it up in your 3D printer and press a button and you got a gun. Its a game changer, especially in areas where buying/selling guns is illegal or difficult.
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There is a big difference. Almost nobody knows how to make a gun. Put all the professional gunsmiths and all the amateur gun-makers that you mention together and they make a tiny fraction of 1% of the population.
Suddenly those "we are the 99%" protests are getting scary.
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Poppycock (Score:3)
OMG! Crazy conspiracy theorists can build bad guns with printers!
BOLLOCKS
Anybody can go to their local hardware store and build a zip gun [wikipedia.org] for as little as $10.
Quote: Keep in mind this should only be used in extreme situations, survival situations, or simply having fun. This homemade 12 guage is simply awesome! [youtube.com]
Dregging (Score:2)
Printed Rifle? Nah. (Score:2)
The Grizzly "rifle" fires a 22LR round which is useless in self defense situations.
Regardless of it's external shape, this is probably a regression in development of 3D printed firearms. Especially considering the load pressures, both the 380 ACP and the 22 LR are around 20,000 PSI to 25,000 PSI.
A real rifle round? Well your looking at anywhere from 50,000 PSI (such as the 7.62x51mm NATO aka M14/M24/SR
Some help from composistes? (Score:2)
I wonder how the Grizzly would work if the barrel had vacuum formed kevlar composite added to it. I would imagine that it would definitely help hold it together from cracking in the first place along with protecting the person holding the thing if it were to break.
Prototypes (Score:2)
Prototype designs don't always go well, regardless of what they are made of or their intended use...
Success is often built on top of many failures.
Wrong 3D printer technology (Score:2)
If making a gun out of ABS plastic worked, someone would be punching them out by the millions on injection-molding machines. Any material you can run through a hot-nozzle 3D printer will make a lousy gun barrel. If you want a cheap gun, buy a cheap mass-produced gun. There are plenty of them around.
Selective laser sintering, though... With that, you can make parts out of steel and titanium.
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There's still porosity problems with that and as cannon casters over the centuries have found you don't want a gun barrel made of metal that is full of little holes. The stuff made of metal powder that ends up in places like jet engines in also lightly forged to get rid of those holes - so if you heat it up a bit and squash it after laser sintering that will do the job.
Cutting it out of something already forged with a lathe, mill (or for extra geek points electrochemical ma
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using a lathe is more noisier and messy. otherwise I'd have one at home.
cnc lathe is more expensive in the electronics parts as well than a 3d printer and takes way more effort in learning the cutting bits etc.
titanium might work with sls. but those machines cost way, way way more than decent home cnc mills.
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yea cause a 100 watt laser is totally going to weld titanium directly off the bed
there is a reason its called sintering and not welding
perplexing (Score:2)
the remarkable thing about all this 3d-printed-gun excitement is that it's such a non-story. anyone with minimal motivation and dexterity could always have made their own, better guns. the only news is that a complete clutz can push "print".
so, why don't we control ammo? (actually, we do here in .ca - at least on Ontario, you need a firearms license to buy it.)
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in america if some dumbass wants to blow their face off we let them for the greater good
Wednesday Night Special (Score:2)
Considering that it's not as strong as wood (Score:2)
Come on guys, just get a cheap hobby lathe to go with your expensive 3D printer, spend a couple of weekends learning how to use the thing, and then you can use materials that make a bit more sense for your hobby guns. Making gun shaped plastic hand grenades without a timer is a bit silly.
laser sintering (Score:2)
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Re:A new slogan (Score:5, Insightful)
They would humor you. Rednecks already own a number of real guns and would assume you were some sort of city idiot. Once they figured out that you weren't going to blow off your hand they would go home.
Re:Not to worry (Score:5, Informative)
Only a matter of time before the composites and process improve to the point where it will withstand these stresses.
Inconveniently, 3d printing techniques tend to make doing composites (properly) difficult. Extruder-based designs can use fiber reinforced feedstocks, if the usual parameter-fiddling is done properly; but doing that will mostly just serve to make the difference in strength between the continuous filament (relatively strong) and the bonds at the 'seams' where the newly extruded filament needs to fuse with the previous layer and any adjacent already-laid filament (absolute best case, these might be as strong as the continuous filament, almost always weaker, sometimes markedly so, depending on process control) even starker than it already is, since the reinforcement material won't extend throughout the part (as it does with injection-molded fiber reinforced parts).
Selective laser sintering, while classier, is similarly limited by the fact that the reinforcement material can't extend beyond the boundaries of the powder being sintered (and you can't make the powder particles larger without sending your resolution to hell).
(Now, in the hypothetical cyberpunk dystopian future, it might be possible to produce pre-woven carbon-nanotube/graphene/similar technobabble "sleeves" that would collapse down into easily concealable flat shapes (like a freshly ironed sock); but could be stretched over a simple form and impregnated with a polymer or epoxy to turn them into fiber-reinforced barrels quickly and with almost zero tools just before use, using the same basic techniques used for fiberglass or carbon fiber construction. Not obviously worth it vs. just smuggling normal guns; but it' be a cute trick.)
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Just curious, what's your personal/professional background in knowing all this?
Nothing professional, just some hobbyist fiddling with 3d printers, a bunch of background reading spurred by frustration over comparatively lousy results compared to injection molded parts, and a good, wholesome, upstanding, fondness for testing to destruction.
I certainly shouldn't be treated as any sort of real authority; but it's something that interests me, and I've poked at it at the dilettante level.