First 3-D-printed gun fired, but its digital blueprints make bigger bang

Started by jimmy olsen, May 06, 2013, 07:39:57 PM

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crazy canuck

Quote from: KRonn on May 07, 2013, 01:22:32 PM
Quote from: Malthus on May 07, 2013, 01:02:57 PM
Quote from: derspiess on May 07, 2013, 12:54:33 PM
The cartridge case, chamber, and barrel all take on pressure.

That's not my understanding, and it is kinda contradicted by the existence of integrated paper cartridges. Paper is not a material generally associated with channeling explosive force.  :hmm:

In any event, a plastic cartridge would handle the explosion just as well as a paper one, right?
I think paper rounds were used in muzzle loaders. The powder in the paper gave the right power charge needed. It was poured into the barrel, not loaded like a bullet.  A paper casing would foul a gun as it would leave debris in the chamber and barrel.

If someone wanted to create a weapon to get off one (or a few) shots would this be an issue?

Syt

Quote from: KRonn on May 07, 2013, 01:22:32 PM
Quote from: Malthus on May 07, 2013, 01:02:57 PM
Quote from: derspiess on May 07, 2013, 12:54:33 PM
The cartridge case, chamber, and barrel all take on pressure.

That's not my understanding, and it is kinda contradicted by the existence of integrated paper cartridges. Paper is not a material generally associated with channeling explosive force.  :hmm:

In any event, a plastic cartridge would handle the explosion just as well as a paper one, right?
I think paper rounds were used in muzzle loaders. The powder in the paper gave the right power charge needed. It was poured into the barrel, not loaded like a bullet.  A paper casing would foul a gun as it would leave debris in the chamber and barrel.

http://www.youtube.com/watch?v=Pvc86ggLUY4
I am, somehow, less interested in the weight and convolutions of Einstein's brain than in the near certainty that people of equal talent have lived and died in cotton fields and sweatshops.
—Stephen Jay Gould

Proud owner of 42 Zoupa Points.

ulmont

Quote from: derspiess on May 07, 2013, 12:54:33 PM
The cartridge case, chamber, and barrel all take on pressure. Anyway, I'd like to know what kind of .380 ammo the dude used in his gun.  It's a fairly weak cartridge to begin with, but I'd bet he downloaded the powder charge.

The article claims not:  "[t]he Liberator fired a standard .380 handgun round without visible damage."
http://www.forbes.com/sites/andygreenberg/2013/05/05/meet-the-liberator-test-firing-the-worlds-first-fully-3d-printed-gun/

By contrast, a rifle round apparently blew it up:

QuoteThe printed gun seems limited, for now, to certain calibers of ammunition. After the handgun round, Wilson switched out the Liberator's barrel for a higher-charge 5.7×28 rifle cartridge. He and John retreated to a safe distance, and John pulled his yellow string again. This time the gun exploded, sending shards of white ABS plastic flying into the weeds and bringing the Liberator's first field trial to an abrupt end.

QuoteWilson showed me a video of an ABS plastic barrel the group printed attached to a non-printed gun body firing ten rounds of .380 ammunition before breaking on the eleventh.

Razgovory

Quote from: KRonn on May 07, 2013, 01:22:32 PM
Quote from: Malthus on May 07, 2013, 01:02:57 PM
Quote from: derspiess on May 07, 2013, 12:54:33 PM
The cartridge case, chamber, and barrel all take on pressure.

That's not my understanding, and it is kinda contradicted by the existence of integrated paper cartridges. Paper is not a material generally associated with channeling explosive force.  :hmm:

In any event, a plastic cartridge would handle the explosion just as well as a paper one, right?
I think paper rounds were used in muzzle loaders. The powder in the paper gave the right power charge needed. It was poured into the barrel, not loaded like a bullet.  A paper casing would foul a gun as it would leave debris in the chamber and barrel.

http://en.wikipedia.org/wiki/Dreyse_needle_gun
I've given it serious thought. I must scorn the ways of my family, and seek a Japanese woman to yield me my progeny. He shall live in the lands of the east, and be well tutored in his sacred trust to weave the best traditions of Japan and the Sacred South together, until such time as he (or, indeed his house, which will periodically require infusion of both Southern and Japanese bloodlines of note) can deliver to the South it's independence, either in this world or in space.  -Lettow April of 2011

Raz is right. -MadImmortalMan March of 2017

derspiess

Quote from: Malthus on May 07, 2013, 12:59:17 PM
I don't see why a very hard plastic bullet would not be deadly, albeit not as deadly as a metal one. Again, it doesn't have to be. 

I'm not saying it couldn't kill, just that it wouldn't be nearly as lethal as a metal bullet.  And that it may not be lethal enough to use over other alternatives.
"If you can play a guitar and harmonica at the same time, like Bob Dylan or Neil Young, you're a genius. But make that extra bit of effort and strap some cymbals to your knees, suddenly people want to get the hell away from you."  --Rich Hall

derspiess

Quote from: Malthus on May 07, 2013, 01:05:22 PM
That noted, a hard plastic bullet doesn't have to be as "good" as a lead one - it could still kill people just fine.

I'd imagine it would have to travel at a very high velocity and be aimed pretty precisely to be reliably lethal.

But at this point I think we're talking past each other.
"If you can play a guitar and harmonica at the same time, like Bob Dylan or Neil Young, you're a genius. But make that extra bit of effort and strap some cymbals to your knees, suddenly people want to get the hell away from you."  --Rich Hall

Malthus

Quote from: KRonn on May 07, 2013, 01:22:32 PM
Quote from: Malthus on May 07, 2013, 01:02:57 PM
Quote from: derspiess on May 07, 2013, 12:54:33 PM
The cartridge case, chamber, and barrel all take on pressure.

That's not my understanding, and it is kinda contradicted by the existence of integrated paper cartridges. Paper is not a material generally associated with channeling explosive force.  :hmm:

In any event, a plastic cartridge would handle the explosion just as well as a paper one, right?
I think paper rounds were used in muzzle loaders. The powder in the paper gave the right power charge needed. It was poured into the barrel, not loaded like a bullet.  A paper casing would foul a gun as it would leave debris in the chamber and barrel.

No, that's a different type. I'm thinking of integrated paper cartridges, not the sort where you bite the bullet off and poured the powder down the barrel.
The object of life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane—Marcus Aurelius

MadImmortalMan

Meh. Some things just can't be "controlled". The farther we get into the future the more of those things there will be.


Imagine in Star Trek when everyone with access to a replicator can make whatever they want. Want some crack with your Earl Grey? No problem. Just download the formula on the replicator torrent site.
"Stability is destabilizing." --Hyman Minsky

"Complacency can be a self-denying prophecy."
"We have nothing to fear but lack of fear itself." --Larry Summers

Malthus

Quote from: derspiess on May 07, 2013, 01:35:05 PM
Quote from: Malthus on May 07, 2013, 12:59:17 PM
I don't see why a very hard plastic bullet would not be deadly, albeit not as deadly as a metal one. Again, it doesn't have to be. 

I'm not saying it couldn't kill, just that it wouldn't be nearly as lethal as a metal bullet.  And that it may not be lethal enough to use over other alternatives.

If plastic doesn't work well (and in spite of your repeated statements I don't really see why not - many plastics are extremely hard), why not stone bullets in a smoothbore?
The object of life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane—Marcus Aurelius

KRonn

Quote from: Razgovory on May 07, 2013, 01:30:28 PM

http://en.wikipedia.org/wiki/Dreyse_needle_gun

Interesting, so there were paper cartridges used in some breech loading guns, and apparently pretty effective. Thanks for that link Raz.  I had never heard of that before. And the paper burned entirely when the gun was fired. Should be useable in a plastic gun, though still the plastic barrel may not be able to handle a heavy load for extended time, but something like a .22 caliber may work.

merithyn

Yesterday, upon the stair,
I met a man who wasn't there
He wasn't there again today
I wish, I wish he'd go away...

KRonn

Quote from: Malthus on May 07, 2013, 01:38:04 PM
Quote from: KRonn on May 07, 2013, 01:22:32 PM
Quote from: Malthus on May 07, 2013, 01:02:57 PM
Quote from: derspiess on May 07, 2013, 12:54:33 PM
The cartridge case, chamber, and barrel all take on pressure.

That's not my understanding, and it is kinda contradicted by the existence of integrated paper cartridges. Paper is not a material generally associated with channeling explosive force.  :hmm:

In any event, a plastic cartridge would handle the explosion just as well as a paper one, right?
I think paper rounds were used in muzzle loaders. The powder in the paper gave the right power charge needed. It was poured into the barrel, not loaded like a bullet.  A paper casing would foul a gun as it would leave debris in the chamber and barrel.

No, that's a different type. I'm thinking of integrated paper cartridges, not the sort where you bite the bullet off and poured the powder down the barrel.

Yep, that's what I was thinking of, circa US Civil War type ammo.


merithyn

Yesterday, upon the stair,
I met a man who wasn't there
He wasn't there again today
I wish, I wish he'd go away...

Iormlund

Quote from: derspiess on May 07, 2013, 12:45:33 PM
I'm sure it can contain *a* blast-- just with less powder than what you'd use in a normal gun.  Even with that I wouldn't dare fire it.  And like I said, a plastic bullet isn't going to be a particularly deadly projectile.

:huh: A high density plastic bullet is more than capable enough of killing someone.

And while nobody sane would dare fire it, that's not the ones that we worry about. A perturbed person would be perfectly willing to do so. Or someone toying with suicide. Or even just a kid. That's an interesting angle actually, how are you going to keep children and teens from downloading and printing weapons?

And then there's another angle: what about those countries where guns are rare?


I have a very hostile attitude against censorship but this tech creates quite a dilemma.