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Guy Creates Handheld Railgun With a 3D-Printer (engadget.com)
turkeydance writes: Using a combination of 3D printing and widely available components, David Wirth built a functioning handheld railgun that houses six capacitors and delivers more than 1,800 joules of energy per shot. So far he has tested the gun using metal rods made of graphite, aluminum and copper-coated tungsten. David has shot projectiles at over 250 meters per second in tests.
3D printed handheld rail guns shooting nails?
Do railguns have any potential benefits over traditional powder-based guns?
For values of "hand-held", obviously.
I'd like to see the holster for that.
There are no function related parts in a rail gun that can be 3d orinted. You cant print capacitors or metal rails. Theres even less to print than you could on a normal gun.
AK-47: 715 m/s
.44 Magnum: 360 - 450 m/s
Black powder musket: 120 - 370 m/s
1,800 joules doesn't sound a lot. Without taking my shoes off, it's roughly equivalent to a biggish person running.
who thinks this story sounds like a Plague, Inc. in-game headline?
I need one to deal with desktop wars here (and some clients) :-)
Religion: The greatest weapon of mass destruction of all time
The anti-liberty Libertarians :-)
I'm a minority race. Save your vitriol for white people.
Australia too.
A glorified air gun.
Now just to figure out the size of the battery pack to charge the capacitors, and we can have a new sport - "Extreme Painball".
Don't mis-feed it after midnight and never get it wet.
This thing is less powerful than other youtube handheld rail guns... and the design while funny is not especially practical. Obviously the capacitors need to be mounted on your back or something to distribute the weight more effectively on the user.
*drops mic and walks*
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
The next version will support e-mail too.
Sheesh, evil *and* a jerk. -- Jade
Whoosh
Uh, no. You're probably thinking feet-per-second, not meters-per-second. This is about three times faster than a pellet gun.
Guy Creates Handheld Railgun With a 3D-Printer
His name's David, not Guy.
systemd is Roko's Basilisk.
So the real question is, how can we get more women into railgun development?
I suggest raising money for a female-only railgun school.
That's not a bad guess, but not really true, for four reasons.
First, there is no "moment of detonation", powder doesn't detonate*, it burns quickly, producing gas. It's a lot of gas in a small space, so it's under pressure and that pressure pushes the bullet out. The powder continues to burn as the bullet moves down the barrel and even -after- the bullet leaves the barrel, producing muzzle flash. In pictures you may have seen the "fire" coming out of the muzzle. That fire is burning powder, meaning it's still burning after the bullet is gone.
To look at it from another perspective, imagine a firecracker on a stick. When the cracker blows, the stick doesn't get shot "backward" toward whoever lit it. The recoil exists because (and while) the bullet and gas is being propelled down the barrel. So the duration of recoil force to the slide is the same as the duration of pushing the bullet down the barrel, equal and opposite at any given instant.
Third, slide -momentum-. The mass of the slide means that the recoil force increases the momentum of the slide, and the hand feels the force as you resist the slide's recoil - meaning the hand or other mount feels the recoil until the slide stops, after the bullet has hit the target.
Lastly, the slide -move- relative to the frame (and hand or other mounts) against a spring. Since the slide is pushing on the spring, and the spring pushing on the frame, it's actually the pressure of the -spring- that pushes on the frame. Therefore the mount experiences only as much recoil as the resitance of the spring at that portion of its travel.
* Some powders contain ingredients that -could- detonate if they were pure, but they are mixed with much slower burning components in order to slow them to a conflagration.
It's all relative. The US murder rate is quite low compared to the freedom loving Somalia, Congo, or other similar regions of Africa.
And a hell of a lot more mass than a pellet too.
Awwww, so close.
Only some components were 3D printed. But, you know, #3DPrinting is trending so...
have you ever used a fully automatic weapon? hint, they are worthless for hitting anything after the first round, we'd be better off having them easier to get, as anyone not in the know would gravitate to them and use up their ammo faster.
currently they are not worth the paper work(tax stamp) to obtain.
Higher elemental effect chance. Sweet!
1,000 fps + pellet guns are quite common
love is just extroverted narcissism
The censorship laws you people have tell me that your government isn't exactly concerned about your opinions. I'm a bit concerned about a government that has the power to ban alcohol and pornography whenever and wherever they feel is necessary.
Gamingmuseum.com: Give your 3D accelerator a rest.
American idiots.
Do we need to have a news article every time something new is printed with a 3d printer? Did we do that with dot matrix printers?
If it's meters per second, it's still subsonic.
>it modifies the time profile of the impartation of the momentum to the mount or the person holding the weapon.
and the topic of this thread is precisely the time profile. Quoting: ... (although the recoil is felt longer)
>> detonation time, whereas in a railgun the energy is spent continuously during the time the projectile travels the length of the barrel.
So whether or not the recoil is spread over time is precisely what I was responding to.
I dunno who this "David Wirth" is, but he should definitely rearrange his name to be "Darth Wivid". (Which is kinda what my brain saw anyway when I scanned the description...)
When I read handheld it makes me think more along the lines of the Noisy Cricket ...
What I find funny on this is that I see everybody criticizing the performance of the gun (and some in a very arrogant way) but no one noticed that he did this project for the sheer fun of doing it.
Religion: The greatest weapon of mass destruction of all time
I'm getting weary with all the 3D printing hype that goes on in this community. You do realize that humans have been making 3D objects without 3D printers for the vast majority of recorded history, right? While 3D printers come in handy for making some objects, they are not the sole enabler for making *any* object. Just another tool. Big deal.
So its co2 boosted?
Minimum threshold fixed. Thanks!
You do know that Australians have more guns now than when the 1996 firearms buy backs occurred, right? It was a $500 million wasted to destroy objects that John Howard thought were "evil". That money would have been better spent on the mental health care.
in schools means less school shootings!
Centrifugal pushes apart from the center, while centripetal pulls together toward the center, so the destruction would be from centrifugal force.
The rest of the developed world with its massively lower murder rates disagrees as well as Sweden.
The societies with lower murder rates don't have Hollywood. American entertainment bombards us with ever greater levels of violence. The increase in mass shootings isn't a result of more guns, it is a result of more violence being spread like a disease through our media. If you want to ban something, ban portrayals of violence on television, cable and in the movies.
This is 100% fake.
http://o.aolcdn.com/hss/storag...
1: That's not handheld.
2: That's a CO2 tank.
He's built a paintball gun and put a bunch of shit on it, then added sparks at the end of it.
1800 Joules is way over a fucking 44 magnum (1300-1500). Yet if you look at the videos posted, you can see that when he fires at some particle boards nothing fucking happens. The "article" original claimed it was 3,000,000 Joules. LOL!
If you read the video descriptions on Youtube, he claims:
WXPR Test 3 - 1" long 0.25" aluminum sabot (1.1g total mass). 1.6kJ caps, 500 psi injector. 36" distance to target: angled 3/4" plywood board with 1/4" mild steel backplate. Made a 1/2" deep indent in target and bounced off. Speed was above 250m/s.
Successful proof of concept for repeatable shots on the same set of rails.
So, 1600 J, not 1800. And that tank at 500 PSI is an "injector"? LOL! It's an air gun with some capacitors for no reason!!
His latest video involves shooting a cantaloupe, because everyone laughed when he couldn't penetrate plywood. He claimed they were "steel backed" plywood boards, but he still barely put a dent in them.
Here's the cantaloupe: https://youtu.be/t0vCiafjUy8 He allegedly fires at around 1300 J according to his own LCD display. There's an odd cut at 1:51 in the video as well, so I have no idea what he's actually doing. (Watch from 1:49 to 1:52 at 0.25 speed to see the cut). You can watch the shot in slow mo too.
Here's a 44 magnum shooting a watermelon: https://youtu.be/dYtfq8KdlnE A 44 magnums runs at 1300 J to 1500 J. Do they seem at all comparable?
Comparing the US to far smaller and relatively non-diverse countries like Sweden or Australia on murder rate is a flawed process.
http://www.westernjournalism.c...
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
I can't find an explanation of, what appears to be, a CO2 canister on the back. Is it using CO2 as a propellant (not a rail gun) or a coolant or ..?
Um, that's not what I think of when I hear the word "handheld". That's up in sewing machine weight....
And no, I have never seen the stat that 40% of all households have guns, and I don't believe it.
Finally, the reason some countries have less crime: economically, the 99% is better off, and there's no12% or 20% or 35% of the population that, based on all available evidence, they'll never get ahead, and they'll always be living paycheck to paycheck, and worrying that a health issue, even with "insurance", will take everything from them.
And then there's the living-while-not-white-middle-class-male.
mark
It also ignores the fact that 30-44% of homicides are committed without a gun.
Plus Sweden has it's own police state crime and commitment issues.
A Pirate and a Puritan look the same on a balance sheet.
This guy is lucky he didn't build a clock!
I guess he is more lucky he is white!
The US murder rate in certain cities is higher than the entirety of the rest of the nation. When you look at where the murder rate is high, you might be suprised to find out that they are not places with high gun ownership.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
We have an annoying right wing party that tells people to be afraid of immigrants.
In standard pistols, the breech is unlocked after the slide moves a distance relative to the frame, and the slide continues to move after the breech is unlocked. This movement of slide relative to the frame means that the slide has momentum (recoil energy) that it has not yet transferred to the frame.
Whether that motion unlocks the breech directly, via a tilting barrel, a lever, or a rotary mechanism doesn't effect this fact. So long as the any recoiling part of the weapon is moving faster than the frame, that's recoil energy not yet transferred to the frame. That means it increases the time over which the same energy is transferred and therefore reduces the instantaneous force.
Where this would not occur would be if you had a weapon in which no massive parts of the weapon has recoil motion relative to the frame - mortars and old-fsshioned cannons.
The US isn't all that much larger in area, but the population is a bit more than proportionally larger. That's probably what you meant, but it wasn't clear from your post.
OTOH, gun control in the US dates back to the 1870's (or perhaps earlier). And there are arguments that it's reasonable in dense population centers. Like Dodge City in the 1870's.
I think we've pushed this "anyone can grow up to be president" thing too far.
So you're saying we have crime because of all the non-white people?
In what way is that not racist?
And linking to westernjournalism, that's rich.
So you're saying we have crime because of all the non-white people?
In what way is that not racist?
And linking to westernjournalism, that's rich.
Simple: anytime you have vastly different cultures mixing and colliding - blacks, whites, asians, muslims, christians, atheists, or even among same race but different ethnic groups like Italian, Jewish, WASP, Irish, etc.. -you get the picture- you get more tensions and friction, as the "melting pot" rarely brews smoothly at first. It can take decades (or centuries) for things to homogenize; in the meantime, this friction breeds mistrust, racism, bigotry, or just plain old fashioned differences of opinion; all this can lead to victimization and also feeling victimized, in an ugly cycle. Violence sometimes breaks out. And that most certainly includes whites of all ethnicities in that mix. It's not the only factor in the violence equation, but it is a factor as it means a more complex demographic.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
Clearly, from the picture, the railgun does not fit nicely in a backpack. But it's still cool looking.
You know, it really isn't.
Downmodding is the refuge of the weak. Don't downmod, make a better argument!
It's slashdot, you can safely skip the first thread on anything posted here. It's just off topic attention whores wanting to be near the top of the page.
Cap gun
You are a moron. 250 meters per second is only 820 feet per second. That's not even a good pellet gun.
I guess that's why the video showed the projectile bouncing off of the plywood backstop. A pellet would have gone in or through.
That's a great video. The extreme limp-wristing allows us to see what the different parts of the gun do without too much interference from the hand.
Kinetic energy is mass (weight) multiplied by velocity.
Here are the mass measurements of different parts of my Glock 19:
Slide 12.3 oz
Barrel 3 oz
Frame and the rest 6 oz.
So we see that if they were moving at the same speed, the slide would have twice as much energy as the frame.
You can see in the video you linked to (and by the fact that it moves backward relative to the slide) that the velocity of the slide is GREATER than the velocity of the frame. Therefore more than 2/3rds of the energy is in the slide until it stops moving rearward relative to the frame.
This may surprise you. Still, mass times velocity. It's not just a good idea, it's the law.
Yahoo said the gun has 3000 kilojoules (3,000,000) joules of energy per shot! This article actually seems accurate, thanks Slashdot I was curious about the actual energy generated by the gun. 1800 joules seems very reasonable
Especially when the outcome is not guaranteed.
Something that has occurred to me is the possible use of a nuclear detonator technology developed by Lawrence Livermore National Labs called a "Slapper". A slapper, used to propel mass at high velocities, overcomes some engineering problems with railguns by not fighting the vaporization of metal in the ammo, but rather using it as the propulsive "gas" behind a dielectric material which can be made refractory.
Seastead this.
wait, what, Australia is non-diverse? I assume you mean culturally? about the only way you could get the non-diverse label to stick would be that Australians are reasonably united in not wandering around with guns for no really sensible reason.
While I agree with the pornography, the alcohol side is actually a good thing in 99% of the places where it is implemented.
Australia isn't quite as diverse as the US is, nor nearly as populated. It's also an island, surrounded by ocean, which makes smuggling guns a bit trickier than a country with several times the square area and a collective approximate 6,000 miles of land border.
Americans don't "wander around" with guns either. Open or concealed carry is not that common, and even where it's legal doesn't mean everyone is doing it.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
40% of murders committed without a gun?
Then England has the same per-capita murders as America.
Oh, wait, obvious LIE!
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