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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.
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
For proof and pudding, look to the US Navy's Railgun program. They have successfully shot test projectiles at Mach 8, the end-game is a reliable system to fire 10KG round at Mach 7.
Keep in mind the speed drops dramatically after exiting the barrel/rail assembly.
If only criminals have guns it will be damn easy to identify them and lock them up.
True-ish, but the devil is in the details... you'd probably need a lot more law enforcers to be able to do that. AKA a "police state".
Sweden respectfully disagrees.
it's in my head
No, railguns suffer a lot of wear in the rails.They get a lot of friction and need to be replaced. The heat generated damages the metal too (bends or cracks, so you want high quality rails), and you want to keep the rails perfectly straight.
If only criminals have guns it will be damn easy to identify them and lock them up.
True-ish, but the devil is in the details... you'd probably need a lot more law enforcers to be able to do that. AKA a "police state".
I, for one, prefer a society were it is generally acceptable that individual members take some responsibility for their own well-being. I always thought the liberal mindset is all about the individual and his liberties.
The rest of the developed world with its massively lower murder rates disagrees as well as Sweden.
Yes - though not at the level of the one in TFA and probably, for the foreseeable future, only in the realm of large naval guns (and possibly - slightly further down the line - guns mounted on tanks or large aircraft).
With a traditional naval or tank shell, much of the damage comes from the explosive contents of the shell (which tend to be quite sophisticated in their design these days). The downside of this is that the ship or tank ends up carrying a substantial quantity of explosive material, just waiting to be set off. Magazine explosion is a particular danger for ships.
Railguns, by contrast, fire inert slugs. The damage comes from the (much) higher velocity at which the slug is fired, which translates into much higher kinetic energy transfer on impact. This means that the ammunition tends to be smaller (so you can carry more of it) and safer. The higher velocity also has significant potential benefits in terms of accuracy.
The US Navy is currently conducting real-world tests of railguns on ships and there has been a lot of progress over the last few years. The challenges include the high power requirement and the need to replace rails regularly (due to the extreme stresses associated with each firing), which can substantially harm rate of fire.
Practical handheld railguns which offer significant benefits over existing firearms are still a long way off (if, indeed, they ever happen). The one in TFA has a muzzle velocity which is at the low end of the range for a "traditional" firearm, with significantly lower convenience (and some quite worrying looking safety issues).
Sweden actually has a pretty high gun rate per capita due to our big hunting community.
However, with gang shootings becoming an every day occurance in our ghettos and our tiny police force strained from uncontrolled immigration things are about to get ugly.
The crime statistics don't seem to support this.
Hold my beer and watch this!
Yeah, you and your appalling ghetto murders unconstrained by your tiny police force - all 0,7 murders per 100k population per year. How do any of you survive? (US = 4,7 murders per 100k per year)
What are you doing on the net - don't you have a Sverigedemokraterna party meeting to attend?
The War of 1812... the good 'ol days when the federal government actually tried to save New Orleans.
Unfortunately, the "Mach 8" version is ridiculously long and only works once. It needs rebuilding between shots, and is ridiculously expensive. It's easier, and more aimable, to fire an ICBM. The allegedly more practical versions can be safer on a nuclear vessel, which has a prodigious and stable and well well armored power supply, as opposed to having an armory filled with chemical propellant powered munitions that have to actually be loaded, full of chemicals, into the weapons on deck.
They've also really not perfected projectiles without electrical contact with leads on the railgun's launching rail. Those leads tend to wear out *really fast*, much faster than the rail gun builders like to admit: it's been a limiting factor since the first designs, once that keeps being "solved" with a lot of handwaving that has never worked well. Kind of like garbage collecting in Java, actually....
Umm, the primary round shot from a tank gun is APFSDS (Armor Piercing Fin Stabilized Discarding Sabot). It's a big dart. No explosive at all.
"I do not agree with what you say, but I will defend to the death your right to say it"
Please! Do no obscure the debate with facts!
"Uncontrolled immigration", yeah... Another one that has drunk the cool-aid of the now-said-to-be-reformed-racist extremists. The likes of you are more a part of the problem than the solution.
I used to live in one of the said "ghettos" for the first 25 years of my life, and believe me, the crime rate there isn't higher than in the central parts of the big cities, quite the contrary. Also ghetto is a very strong word, so I guess that you have never set foot in one of these areas, nor seen a real ghetto, or else your retorics would be quite different.
The problems in Sweden are with criminals, not immigrants per se. Anyone alienated from society have to find new ways to get by and most does in peaceful and meaning ful ways, forming their own groups within society (sad to see competence wasted this way because we are too stupid and stubborn to let good people find good work). A few turn to crime, but from the criminals I have met more have had "pure" swedish background than being first or second generation immigrants.
But making up "facts" to support one's twisted world view is standard practice within these extremist circles, so I am not surprised at all.
... or, for that matter, shoot things *out* of orbit (much harder from an aiming perspective, much easier from an energy perspective; the "warhead" would be sand scattered like buckshot by explosives)
The War of 1812... the good 'ol days when the federal government actually tried to save New Orleans.
The electrical effects are pretty brutal, as well. The two rails function as bus bars, with the conductive projectile completing the circuit. Given the fairly heroic currents required to get useful projectile velocities, you are squeezed between trying to reduce resistance(which makes driving the railgun easier and makes for less arcing and resistive heating; but involves more contact area between the projectile and the rails, and greater mechanical wear) and trying to reduce friction(which reduces friction heating, mechanical wear, and slowing of the projectile by the rails; but tends to increase resistance, encourage arcing and electrical damage, and so on).
Your ideal rail/projectile interface would be a frictionless superconductor; a flavor of unobtanium that is in short supply at present. By throwing enough power at the problem, and treating much of the rail assembly as sacrificial, you can get pretty impressive results; but if you thought that barrel erosion sucked in gunpowder weapons...
The main problem with magazine explosions in warships or tanks is the propellant charge, not the shell filling. Shells are generally pretty insensitive and the bursting charge of an armour piercing shell is comparatively small.
Obviously rail guns remove the risk of propellant and warhead explosions, but the price is no indirect fire. Naval gunnery is mosty used for shore bombardment these days, firing at targets behind a hill isn't going to happen with a railgun.
While "traditional" tanks rounds were explosive, modern ones are generally kinetic, but ammunition explosions are still a risk due to the propellant. Surprisingly some WWII tanks fired solid shot at the start of the war, but almost modern APDS rounds appeared in 1944.
It's never too late to have a happy childhood.
tiny police force strained from uncontrolled immigration things are about to get ugly.
It's nice to be able to hide one's racist views behind the anonymous moniker, isn't it?
With a fascist government you wouldn't be able to.
it's in my head
The next version will support e-mail too.
Sheesh, evil *and* a jerk. -- Jade
This part has always bothered me. Why do the rails have to be straight? Would rails spiraled to match the Lorenz force work better? Think DNA. Bonus the round would leave the barrel with rotation adding accuracy and trajectory stablization. Also it would work better for exterior force pushing agonist the rails as round shapes deal with pressure better.
i thought once I was found, but it was only a dream.
Apologies - you're correct. I allowed myself to get stuck back at the WW2-level for tanks there. Warships, however, do still fire explosive shells, as do land-based ballistic artillery pieces.
Guy Creates Handheld Railgun With a 3D-Printer
His name's David, not Guy.
systemd is Roko's Basilisk.
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.
Only some components were 3D printed. But, you know, #3DPrinting is trending so...
1,000 fps + pellet guns are quite common
love is just extroverted narcissism
Unfortunately, the "Mach 8" version is ridiculously long and only works once. It needs rebuilding between shots, and is ridiculously expensive
So its perfect for the US navy.
In the free world the media isn't government run; the government is media run.
That, by definition isn't a railgun, though they're often mixed up in reporting.
What you're thinking of is some sort of linear induction motor. The simplest sort is a gauss gun. Those are easier to build than railguns. Basically you take some sort of iron core, i.e. an iron pole and build a biggish electromagnet on one end with an emphasis of a small number of turns of relatively thick wire. Drop an aluminium ring on to the pole and use a big capacitor bank to dump current into the electromagnet.
The easiest way to do that is wire it in series with a camera flash: that provides the high voltage, high current circuit and a camera flash is a moderately efficient, moderately fast switch.
You can get reasonably impressive results that way.
There's no levitation, but no contact is required between the projectile and the barrel so you don't get bad barrel ware.
There are lots of variations of this. You can have multiple stages. You can also have many many stages and wire them up in groups to 3 phase making essentially an unrolled 3 phase induction motor. One of those used to feature at the Cambridge University Engineering Department open day and I saw it operating when I was a kid. A fairly small one (a meter long) could fire a copper/steel slug through a decent sheet of plywood (after blowing a breaker).
There are variations on linear motors which do have levitation, but I think the annular motors are more efficient since they're pretty good solenoids and so you get better flux coupling.
The local power source in all those cases is induced current in the slug from the magnetic coils. In a true rail gun the current goes through the projectile.
SJW n. One who posts facts.
Facts which surprise most people:
1) Not just today, but even in WW2, generally or very often armor piercing tank rounds were solid shot.
2) The amount of explosive in one of the shells of old battleship big guns was rather ludicrously small. The Mark 8 AP armor-piercing projectile for the 16 inch gun had a complete weight of 1225 kg, of which 18.55 kg was the explosive charge. Even the Mark 13 HC "high capacity" non-armor-piercing projectile intended for purely explosive effect, which weighed 861.8 kg, had an explosive charge of only 69.67 kg. That's right: even the smallish Mark 82 general purpose 500 pound bomb, which weighs 232-259 kg with an explosive charge of 89 kg, makes a bigger bang, and did so in WW2 too. The more impressive Mark 84 general purpose 2000 pound bomb packs 428.6 kg of explosive charge and makes the 16 inch round seem puny.
Over the years, the big guns have acquired an aura of supernatural power which was never justified from the standpoint of bang. What remains impressive is that they could penetrate a foot of homogeneous steel armor at perpendicular impact BEFORE exploding. Supposedly they could penetrate 10 meters of reinforced concrete (I believe the last to be a gross exaggeration, given that armor piercing bombs of 5500 kg had trouble penetrating the 3-5 meter concrete roofs of U-boat pens).
Incidentally, when fired from the Mark 7 16 inch 50 caliber gun of an Iowa class battleship, these rounds were propelled by 299 kg of "smokeless powder" (which was neither smokeless, nor was it anything like a powder in form) hand-placed in the loading tray in the form of six 50 kg silk bags.
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
Posting anon since I work with the Dahlgren EMLF (Electro-Magnetic Launch Facility)
I'm not going to comment on specs, but the current test launchers (to my knowledge) does not require rebuilding every shot (even with higher MJ launches). They did about 6 years ago. The navy's final launcher also is going to fire at rates over 9 / min, which puts a lot more load on the rails and power supply system (and other things). This is part of why it's taking awhile to develop. Compressing a building's worth of equipment down to fit in a ship is also non-trivial.
It's not particularly expensive to shoot. I have been told there are some times we do shots as opposed to using modeling because it's quicker, cheaper, and is better data. The missile development people would kill for something like that.
There are some issues with rail wear, but a round only ever gets fired once, so the electrical destruction of the round that occurs only has to not affect the aerodynamics of the round for that shot.
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?
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?
No, the spring/gas system in the stock eats up the recoil. Learn how yours guns are constructed.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.