Rail Gun

[ShawnDow]

So I have been looking into rail guns and how they work... in theory any way. Has any one on here ever experimented with making one? Or better yet has any one ever used such a mythical sic-fi contraption?

I have the urge to start tinkering with one... My only concern is that I'd be "manufacturing" a "firearm" ; well technically a firearm uses a propellent fuel or compressed air as a means to shoot a projectile... so would I really be making a "firearm"?

any way... its time to start small scale... like bb / pellet gun scale and work from there...

Darn A.D.D. see what you started!

well if its not legal, please, some one let me know... I don't want to break the law here. And if I need an F.F.L. to be able to build this... would any of you out there (with one) want to venture into this journey with me? I have Ideas... just need the legality.
well have fun chewing on that one..
Shawn

[JLA]

youve been playing too much Metal Gear Solid.

[skullfr]

make a punkin chunker.They fire really well and legal

[ShawnDow]

I'm 39, Metal gear solid is well AFTER my time... I like physics...I just didn't know if it was possible to make such a contraption (relatively cheep and effective) even if all I can do is shoot B.B.'s . I mean come on... the military spent our tax dollars developing one, and it will shoot 26 miles... I just want 100 yards... can I make one? And don't tempt me on the pumpkin chunkin' thing... I already made a spud launcher capable of 200 yards back in the day.

[JLA]

A hobby cannon made of a section of drillpipe, that just so happens to have a golf ball sized hole in it is quite fun shooting golfballs under a quarter pound of BP.

And come on, Nobodys too old for MGS.

[shorter260513]

You could make one but it wouldnt be anywhere near cheap by the time you put enough transformers and caps together no way portable. Wouldnt say impossible but not feasible just the power to run it would be just as dangerous as the projectile thats just my opinion.

[shorter260513]

As far as legal I dont thing the BATFE has any regs that cover such a weapon but its usually never a good thing to have a law named after you

[ShawnDow]

Originally Posted by shorter260513

As far as legal I dont thing the BATFE has any regs that cover such a weapon but its usually never a good thing to have a law named after you

Come on... DOW Jones... DOW Chemical... (YES I'm related... NO I don't get money from them; related to the Farmer of the brothers ) DOW anti-electromagnetic gun law... Your right.. it doesn't sound too good!

Im just curious as to how loud they are compared to regular "metallic cartridge" guns.

[shorter260513]

check out powerlabs.org they have a railgun even show a couple videos I think the dump of the electricity makes it pretty loud

[skullfr]

Hey Im 57 and still play video games.I play online game called Aces High II.I got almost 400 bucks in controllers.I had to attach a shoe to the rudder pedal to operate with one leg.My computer was custom built to play the game.

[ShawnDow]

Skullfr... if you imagine all that electronic stuff you have there, and visualize a micro mill, micro lathe, wan'a be gun shop / reloading shop, and "imagination station"... you have my work shop... I gave up on the gaming when my boy started kicking my butt at them when he was 8... now he is 15... Now.. when he invents something and produces it.. Ill give that up too.

Shorter260513 as for that web site... I want my work shop to be like that!

[Twicepop]

Originally Posted by ShawnDow

Skullfr... if you imagine all that electronic stuff you have there, and visualize a micro mill, micro lathe, wan'a be gun shop / reloading shop, and "imagination station"... you have my work shop... I gave up on the gaming when my boy started kicking my butt at them when he was 8... now he is 15... Now.. when he invents something and produces it.. Ill give that up too.

Shorter260513 as for that web site... I want my work shop to be like that!

I did a small ammount of research on these, probably enough to get into trouble, but.... These use a tremendous ammount of electricity to fire a projectile, but the energy that the projectile produces is beyond anything imaginable with conventional weapons. The cratering effect the projectiles have is much like that of a meteorite, picture the impact crater in Arizona, but on a smaller scale. From what I can understand of the procedure, the projectile has to floats upon an electronic flux field, with no part of it phisically touching anything. To then launch the projectile it must still float on the flux field and then be transported forward by a series of discharge capacitors, the speed being determined by the length of the capacitor field and the the speed of which the capacitors discharge their energy. Impact velocities are measured in yards per second up to miles per second. I'm not a scientist, and don't play one on TV, so if anyone has anything to add or correct feel free to do so.

those who beat their guns into plowshares, will plow for those who didn't

[Blackhawk Dave]

First you have to have a series of magnets that will allow the "bullet" to float. Then you have to be able to change the polarity of the magnets so that one pushes, one pulls, and changes polarity as the "bullet" passes through the fields....very fast.

I don't know about you but my PC just could not handle that. Let alone the power needed to generate any sort of speed. That's why they're being planned for ships, which have the very large generation facilites on board, as opposed to being mounted on an airframe.

[howlnmad]

I think someone has watched Eraser one to many times.

[pkcgbifaid]

I graduated with a degree in Engineering Physics in the 90's and a guy that graduated the year before me built a small scale version that was a little different than what you are thinking about. First, his "rail" was a solid cylinder with all the electronics and his projectiles were more like a thick washer that slid over his rail. I don't know how expensive it was, but he was a college student so I can't imagine it was crazy expensive.

It was basically just a table top version that pointed straight up. His best "projectile" would only go about three feet up. Unless he cooled it that is... if he froze it in liquid nitrogen first it would bounce off the ceiling. (He almost shot a light out the first time he tried it).

[JLA]

From what i gather about them the magnets have to be supe strong and the projectile has to be non magnetic.. They consume enormous amounts of energy. But i did read last year or the year before that some russian physics student built a shoulder fired one. Might google it.

[Brian Albin]

If I understand correctly, there are two varieties of Rail Gun. One uses nonferrous projectiles and the other uses iron so they can be magnetically driven.
I saw the first type demonstrated on a science TV show. Unfortunately the fool who made it did not take the trouble to make a bullet. He had an aluminum nut he pulled out of the hardware drawer and shot that at his chronograph. He got no reading and said that showed that the velocity was so high it exceeded the capacity of his chronograph. I thought it more likely that with the aerodynamics of a thrown car tire, the nut simply went winging off toward the side wall of his work shop and missed the detector screens entirely.
This aluminum bullet type does not use magnets. It somehow drove the bullet with two loop currents of electricity.

The iron bullet variety needs a battery of electromagnets placed along the rail. These need their polarity changed as the bullet passes along so that the magnets in front of the bullet are pulling it, and those behind are pushing. Perhaps the bullet would need to be a permanent magnet for the push to work. Getting the timing right as the bullet accelerates would seem to be the tricky bit. But I do not think a computer program would need to be written to control it, as it does not seem to me that you need to get it right on the first try. You could set them to pulse at some predetermined guess of a pulse rate, and then adjust it until you get a shot.
Alternatively, a more elegant solution is to have detectors along the rail detecting the presence of the bullet and triggering the change of polarity.

[jack404]

i always thought the timmins tesla one was best

a ferrite magnet inside a sipplery tube that was wound round by a wire ( electromagnet but different polarity of the ferrite cores base) the electricity goes up the wire fast and creates a magnetic field as it goes and this repels the ferrite core in the "slippery tube" and out it goes , they got 800 yards with a 5 lb core but it wasn't near good enough when a then 5 lb'er had a range of 8 miles

if i remember he tried to increase speed but was limited by the speed of electricity along the wire minus the effect of it being wound , and if wound too far apart it did not generate enough momentum in the core ... so say a 4" bore yeah but 800 yards is ok too

its in one of the Tesla books

[jack404]

now as electricity "speed" aint constant we gotta work it out with some assumptions

2mm wire wrapped

100 amp's of juice to "give it some herbs" ( tool time "MORE POWER!!!)

[jack404]

so roughly if tight wound we get 841 meters per second

then divide that by 12.2

or about 69 Meters per second or 230 fps

[targetacqmgt]

Originally Posted by ShawnDow

I'm 39, Metal gear solid is well AFTER my time... I like physics...I just didn't know if it was possible to make such a contraption (relatively cheep and effective) even if all I can do is shoot B.B.'s . I mean come on... the military spent our tax dollars developing one, and it will shoot 26 miles... I just want 100 yards... can I make one? And don't tempt me on the pumpkin chunkin' thing... I already made a spud launcher capable of 200 yards back in the day.

Usually rail guns are HUGE- the US NAVY will has test fired one ar Dahlgren Va weapons depot. Some of the tech is described. If I read the article right the power needed to fire the bloody thing will be a on board nuke reactor. I think I remember the "slug" will be an 8" in dia titanium metal. The slug will travel at least 8000mph though Dalgren is trying to boost the speet up higher. Rate of fire is near a conventional naval cannon. ThE NAVY intends to deploy them on nuke powered vessels by 2015. Your problem is POWER even for a BB and of course earth gravity.

IMO PRC lunar bases(in ten to fifteen years) will have some form of rail guns to take out cities down the earth gravity well. IMO we are financing the PRC's military and space prgrams with the interest we are paying them on the 2 trillion dollars in our t-bills that they hold. Old gunnersmate

[targetacqmgt]

Originally Posted by pkcgbifaid

I graduated with a degree in Engineering Physics in the 90's and a guy that graduated the year before me built a small scale version that was a little different than what you are thinking about. First, his "rail" was a solid cylinder with all the electronics and his projectiles were more like a thick washer that slid over his rail. I don't know how expensive it was, but he was a college student so I can't imagine it was crazy expensive.

It was basically just a table top version that pointed straight up. His best "projectile" would only go about three feet up. Unless he cooled it that is... if he froze it in liquid nitrogen first it would bounce off the ceiling. (He almost shot a light out the first time he tried it).

Interresting- I wonder if Dahlgren is using a liq nitrogen to cool their 8 incher of tungsten.

[targetacqmgt]

Originally Posted by jack404

so roughly if tight wound we get 841 meters per second

then divide that by 12.2

or about 69 Meters per second or 230 fps

Jack has anybody got anything that will go in increment of C velocity? I guess the Univ of Alaska at fairbanks has yet to figure out a magnetic "bottle" to hold a fusion reaction in AND the ability to switch the bottle " on and off"

[CHW2021]

Kinda on the subject, look at the "pumpkin chunkin" guns that were on tv last year for ideas with compressed air ect. Neat stuff and since they fired vegetables they couldn't be called guns, could they?
http://www.punkinchunkin.com/

[ShawnDow]

So if I'm shooting vegetables... its not a gun? So... freeze a pea... .308" and load it like a 30-06... what do you think? NO... sounded good though... that would be one for CSI to figure out.