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View Full Version : Electronic Gun shoots .375" round ball.



gary350
10-29-2009, 04:36 PM
I have been playing around with electronic magnet railguns for years just for fun so I finally got serious and built a real nice gun. All the electronics are built inside the rifle stock. It looks like a short barrel rifle with a gun stock and it all runs on a small rechargable battery. I can shoot a .375" diameter round ball all the way through a 2 x 6 board. I put a 2x6 and 1x6 board together and it will shoot all the way through them both. The best part is the gun is totally silent and BATF can't do anything about it. The only sound is the ball hitting the boards. It is fairly accurate at close range I can put a round balls in a 2" circle at 30 ft. It will make a good snake gun and be good for close range protection. It is a single shot gun. I can reload in 10 seconds, recharge in 30 seconds, and shoot again. I have already figured out a way to reload in less than 1 second and recharge much faster. It would be nice to recharge in 1 second but I think 10 seconds is practical for now.

davidh
10-29-2009, 05:35 PM
pictures and details ? ? ? ?

DebosDave
10-29-2009, 11:03 PM
Yes, we need more information for sure..

On a side note, while they can't do anything about the sound your rifle makes, they can do something if the overall or barrel lengths are too short.

Have you had a chance to chronograph how fast the ball leaves the muzzle? What do the balls weigh?

Dave

38_Cal
10-30-2009, 12:54 AM
Yes, we need more information for sure..

On a side note, while they can't do anything about the sound your rifle makes, they can do something if the overall or barrel lengths are too short.

Have you had a chance to chronograph how fast the ball leaves the muzzle? What do the balls weigh?

Dave

I think you might be off in your assessment, Dave. I'd bet a hot cup of cocoa on a cold, rainy night that it would fall under the same class as airguns...though some states might have regulations on the technology. (Probably the Peace Loving People's Socialist Democratic Republic of California)

Still, very cool idea, and I would love to learn more about it! :cool:

David

BigBoy1
10-30-2009, 06:26 AM
If there are no laws now that apply, our "wonderful" politicians will soon come up with them. I can see it now, metal balls and rechargable batteries will soon be in the same situation as ammunition is now currently in -- Short supplies and high prices!

DebosDave
10-30-2009, 09:47 AM
I think you might be off in your assessment, Dave. I'd bet a hot cup of cocoa on a cold, rainy night that it would fall under the same class as airguns...though some states might have regulations on the technology. (Probably the Peace Loving People's Socialist Democratic Republic of California)

Still, very cool idea, and I would love to learn more about it! :cool:

David

You could be correct, I suppose I hadn't thought of it that way. I was looking but haven't found it so far, as to what the ATF would actually consider under their jurisdiction. But I do think you are right this would more likely all under an air-rifle than a firearm.

Sorry

rws
10-30-2009, 10:19 AM
I would like to see pics too! It obviously shoots under the speed of sound, or it wouldn't be silent, per se.

loose nut
10-31-2009, 02:23 PM
At what range did you get that penetration, of the boards,

You could make it like a pump action shotgun for faster reloading but recharging faster could be a problem. Find a friendly electrical engineer, better yet a high energy physicist.

andy_b
11-01-2009, 02:33 PM
the ATF currently only regulates "firearms". their definition is a device using a self-contained cartridge with some type of propellant in it to propel the projectile down the barrel once ignited. airguns and railguns do not fall under their jurisdiction. yet. :)

rifles with electronic primers (fired by an electric pulse and not an impact) are still covered since they use a self-contained cartridge.

andy b.

DebosDave
11-03-2009, 04:45 PM
Appreciate it Andy!!

We definately need pictures and specs!!

Dave

ulav8r
11-04-2009, 10:38 AM
I tried to post last week about the charge time. Use two battery and capacitor systems. After firing the first time, switch to the second system while the first is recharging. You will only have to wait half as long between shots that way.

You could also consider a larger, multiple power supply on a pack board to avoid increasing the weight of the gun. A 5-10 lb. external power supply should be reasonable if the faster cycling is very desirable.

Forestgnome
11-05-2009, 09:46 AM
A battery-powered rail gun that shoots a 3/8" ball through a 2by? I'm thinking you'll never see a picture of it unless it's created on Photoshop. Think of the energy needed. Really.

malbenbut
11-05-2009, 12:51 PM
I think Gary 350 is extracting the p*ss.
MBB

Alguy
11-05-2009, 03:58 PM
MBB would the term porky pies be the correct british slang term?

malbenbut
11-06-2009, 07:23 AM
quote from alguy
[MBB would the term porky pies be the correct british slang term?]

YES!
MBB

wierdscience
11-06-2009, 12:23 PM
I'd like to see it too.

As for the law,well remember the DC ban? It targeted "Projectile weapons" that's anything from a slingshot to a .50cal.Luckily it didn't stand up.

radkins
11-06-2009, 07:20 PM
Hmm, Just thinking here. There should be more than enough energy stored even in a couple of D cells to shoot that ball through a pine 2x4, at least one time anyway, it's just that the trick would be to make that energy available all at once. Use the energy from the cells to charge some capacitors maybe?

malbenbut
11-07-2009, 05:00 AM
It's been over a week since gary 350 started this thread and hasn't answered any of the replies. Come on Gary details or are you just full of bulsh*t
MBB

Pete H
11-07-2009, 09:44 AM
Could be "trolling" to see if anyone bites... I notice one of his earlier posts dealt with a short-barrelled shotgun, another no-no.:confused:

motorcyclemac
11-07-2009, 06:57 PM
Uh....fertilizer methinks.

The earlier posts about the shotgun...and what have you make me question this chap's merit.

Something funny about all this...

A 3/8th ball bearing from a sling shot wouldn't penetrate a 2by. Hell...it would simply make a nice dent. It would take some serious energy...to push that thru. You aren't going to get there with batteries. Maybe a power source plugged in the wall..charging a bank of capacitors dumping to a helluva lot of electro magnet coils.. But then there is the issue of barrel length to achieve the velocity needed to make the kind of energy to get thru a 2by. I am thinking that a 3/8th inch steel ball bearing probably weighs around 125 grains. I would bet you need to see 750 fps minimum to 1000 fps to get that ball thru a 2by.

Even a bank of rechargable drill batteries couldn't dump energy fast enough to make 750 fps..

I bet the ol' boy has some green grass and tall flowers at his house...

Cheers
Mac.

BigBoy1
11-08-2009, 06:15 AM
Perhaps the lack of a reply results from the person's tinfoil helmut being untuned from the passing UFOs.

BillC
11-08-2009, 11:08 AM
I would bet we will never see a drawing on this project he does this on PM site also.

motorcyclemac
11-09-2009, 10:30 AM
That is the funny part about the internet. Folks use the same screen name and then scatter crap about like that.

I have nothing against using the same screen name...I do that myself. It is almost funny how a fellow like our ballistic engineer figures that no one will notice the same act on another site.

Cheers
Mac.

xarlock667
03-17-2010, 03:17 PM
I came across this thread when I was researching the site looking for help last night. It was part of what made me join the forum.

There are a couple of misconceptions I noted that I might be able to clear up. I have studied physics a bit, and railguns in particular (Would love to build one, but lack the funds.

First, the power to a rail gun must come from capacitors. The power wave must be digital, and not analogue, or you will have **** for results. The wave must be a square, or a sudden charge, or the projectile will roll out of the barrel instead of fly. The reason for this is that only while in contact with the rails does the projectile accelerate.

Second, Batteries are great for charging capacitors, and most will be fine for that purpose, it just becomes a question of charge time, and who many shots you can get out of one. If you doubt the power of a battery and capacitor, I invite you to try the fun experiment of touching a live taser or stun gun. Most of the old ones ran on a single 9v battery, and put out 50kv or better.

Third, while you can make a rail gun fairly easily, the problem is that 50kv hitting a metal object tends to fuse it in place. A lot of rail gun enthusiasts have opted for using injection as a means of making the projectile fire, as it is less likely to fuse if still moving.

If you want to build one, this is the base pattern:
Take 2 metal bars of equal length, and preferably good conductors. Seperate them by an equal distance, parallel, and bolt them in place to a nonconductor. (I have heard of plexiglass being used, but do not quote me.)
Hook your power lines to whatever end you want to be the rear, and then drop in your projectile. Hit it with your power source, and it will either:
a) fuse in place;
b) rocket down the rails and hit something;
c) catch fire; or
d) short out and blow up the capacitors.

The thing to remember about these things is that they are dangerous from several angles. **** loads of voltage, heat, an open circuit, and a high speed projectile, all in one little package. It might be better to give your enemy a kit and let him kill himself!

If anyone has the spare time and parts to build one, please post a vid or pic.

If you are good (I mean really good) at math and you want to know how strong it will be before you fire it, then the force equasion is:
f=bild/m^2
f=force
b= strength of the magnetic field in telsa (1kg@1m)
i= current measured in ampres
l= Length of the barrel
d= width of the barrel (distance between the 2 rails)
m^2= the weight of the projectile squared.
This formula was taken from "Principles of physics for science and engineering" by Brown if I remember correctly. It is one of the Schaum's Outlines series.

Forestgnome
03-18-2010, 05:22 PM
Xarlock, I suspect many of the members here understand rail guns. Don't underestimate the knowledge base of the members here. The OP wasn't really talking about a rail gun, which is what you described, but was talking an electromagnetic or solenoid gun. Rail guns don't shoot plain steel balls. The good ones can shoot a plexiglass slug through plate steel though.

xarlock667
03-18-2010, 08:20 PM
A rail gun can shoot anything that conducts electricity, where did you see it shoot plexiglass? Can you post a link?

Aside from that,

I have been playing around with electronic magnet railguns for years just for fun so I finally got serious and built a real nice gun.

He did actually specify rail gun. I am not meaning to imply that anyone here does not know what they are doing, I am just a newbie machinist, but I know railguns fairly well. Some posters I will not quote specified using a drill's batteries, and some said a battery lacked the power to get the job done. I just clarified that capacitors were an integral component, like an engine in a car, or it won't go. Aside from that, the posters were all right on. I had a few issues with his post as well, how did he avoid welding his balls to the rails? How did he get past the friction wearing down the rails every few shots? How did he get enough capacitors in series to push a ball that size to that velocity, with enough inertia to blow a hole in 2 pieces of wood? I have seen them built, and used, but not with that much power.

Forestgnome
03-19-2010, 12:47 AM
Generally railguns work by first developing a plasma, which is what actually gets accelerated, pushing the projectile forward. To create the plasma a sacrificial conductor is placed between the rails. In the case of the plexiglass, a layer of aluminum or copper foil is attached to the rear of the slug. If you were using a steel slug, it would arc and by not fully vaporizing, would weld itself along the ways slowing it down.

xarlock667
03-19-2010, 12:03 PM
Ok, so the plexiglass is used like a sabot round, with an aluminum coating that flashes to plasma, and then it just rides the plasma wave out the end. That would make for a LIGHT projectile, and shotloads of velocity!

I have seen steel shot (BB's), copper shot, aluminum, lead, and various metals. In the case of poor conducters they typically use an alumimum armiture as it flash a low flash point, and will protect the projectile, but I did not know the projectile could ride on top of the plasma though! That makes things much cheaper.

OK, I have decided to build one. I found some plans that make the thing reasonably cheap. It will NOT be big, or fancy, but it will be able to at least kill a rabbit, even if I have to toss it onto the rails. ;) Fried rabbit anyone? If I don't eat it, my wolf will.

I can get suitable capacitors from a disposable flash camera, and I can scavenge rails from somewhere, though I am not sure on that. I have ****LOADS of batteries in my house, (Lots of 360 controllers, and they eat batteries for breakfast) so that is not an issue. I have some 2x4's left over from a construction project that are rigid, and non conductive. And I have a couple fire extinguishers for when the thing catches fire and burns to the ground. This is going to be FUN!

What is a good conductor to use to make the rails that can be easily scavenged? Any ideas?

xarlock667
03-19-2010, 03:33 PM
Ok, I may have found something for the rails, I have a couple of 440 steel sword blades that broke off their handles way back when. No one will miss the blades, and so I won't have to listen to my sons whine. Besides they will have fun with the rail gun too.

I will start a new thread when I start, and post lots of pics and maybe a movie or two.

CLARKMAG
03-28-2010, 11:15 PM
15 years ago when some Space Defense Initiative [Star Wars] hardware was auctioned off, I know someone who got some rail gun capacitors.

If you were a big time defense contractor, you probably got the tour of the rail gun and saw a spinning Copper disc that was the power supply.

This must have been plan B surplus.

After some rail guns and then steam guns, the hardware found it's niche, shrinking coins.

http://i757.photobucket.com/albums/xx220/ClarkM/Quartersoneshrunk.jpg
Shrunken quarter, next to a regular quarter, using surplus rail gun hardware.

Bguns
03-31-2010, 05:43 AM
Calling an electromagnetic launcher a gun, is just plain wrong.

Does not belong in Gunsmithing section...

CLARKMAG
03-31-2010, 10:54 AM
Calling an electromagnetic launcher a gun, is just plain wrong.

Does not belong in Gunsmithing section...

http://www.navytimes.com/news/2007/01/aprailgun070117/


The range for 5-inch guns now on Navy ships is less than 15 nautical miles, Garnett said. He said the rail gun will extend that range to more than 200 nautical miles and strike a target that far away quickly in 6 minutes. A Tomahawk missile covers that same distance in 8 minutes.

Gunpowder barely gets bullets to 4,000 fps, but rail guns get bullets to 10,000 fps. That is a big deal if you want to shoot down missiles.

There are only a few types of long range weapons:
1) Guns, that put kinetic energy into a projectile that propels it all the way to the target.
2) Rockets or jets that put chemical energy into a projectile and the projectile propels itself along the way.
3) Rays that are energy in electromagnetic radiation that travel as a beam.

For every measure, there is a counter measure.
The game is to make weapons that are cheaper than the countermeasure.
When Reagan's Strategic Defense Initiative measure drove the Soviet Union into bankruptcy and dissolved, it was with largely imaginary technology.

Except the rail gun. They had working rail gun models.
That was paraded past zillions.
My father was chief engineer of a defense company, and so got the rail gun tour.

Bguns
04-04-2010, 05:46 PM
Still not a gun..

And how many Megawatts of generating power required to operate a large Rail
Electromagnetic Launcher that can launch 200 miles????

200 miles= non man portable.

Still does not belong in gunsmithing section.

Batteries do not work well at -40....

A compressed gas powered launcher can do the same as the OP...

CLARKMAG
04-04-2010, 06:23 PM
Still not a gun..

And how many Megawatts of generating power required to operate a large Rail
Electromagnetic Launcher that can launch 200 miles????

200 miles= non man portable.

Still does not belong in gunsmithing section.

Batteries do not work well at -40....

A compressed gas powered launcher can do the same as the OP...

Megawatts is energy per unit time.
The power required would depend on how often you wanted to shoot.

I don't think anyone planned a hand held ICBM interceptor.

loose nut
04-04-2010, 07:38 PM
http://i135.photobucket.com/albums/q153/loosenut_bucket/220px-French_Railway_Gun_27627u.jpg

Now that's a rail gun.:D :D :D

Seastar
04-11-2010, 11:05 AM
Here you go ----
http://www.powerlabs.org/railgun.htm
Now you can build a real one.
Bill

bikewrench
04-25-2010, 01:19 PM
OK I am sold i,ll take two----or plans ----or pictures---SOMETHING, As an FFL holding dealer the BATF does not regulate launchers that don,t use a self contained cartridge, That said this sounds like great tech for the home shop and you have to share some of the details. Might make a great nail gun also, or an impulse tool for swaging fitting.

radkins
04-25-2010, 02:55 PM
I agree with Bguns, this is totally off-topic and belongs in another forum. An electromagnetic launcher is not a gun in the sense that this forum is dealing with gunsmithing and electronics discussions should be someplace else. Fellows this forum has the potential to grow and be a lot of help to a lot of people but folks looking for real gunsmithing info will most likely be uninterested in an electronics discussion. What do the rest of you guys think, should we keep the discussions here about powder, lead and gun repair/building/modifying?

JCHannum
04-26-2010, 08:32 AM
I wouldn't get too worried about it. The forum is self regulating and off topic threads will die a natural death from lack of interest.