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Sorry for the long post but its interesting so read it!!
Ok I know I'm gonna get called a dork for this, but for whatever reason my friend and I started talking one night about whether or not it would be possible to make a completely silent sniper rifle with no muzzle flash (I know, future terrorists of America). So without any physical experimentation, only though experiments we put our heads together and arrived on the idea of using magnets to fire a projectile. Both of us having a pretty good understanding of electricty, electromagnetics, and the physics thereof we compiled as many ideas as to the construction of the device as we could then systematically picked them apart and decided why they wouldn't work.
Our first idea was to contain a magnetized projectile between two counter polarized magnets of equal strength to keep the projectile in place and under compression thus inducing kinetic energy when the front magnet was deactivated. Well then we thought about it and there wouldn't actually be any potential energy created by holding it in place with magnets.
Our second idea was to have a magnetized projectile held in place by a physical mechanism and back by a powerful electromagnet that when turned on would repel the projectile away from it at a high speed. This wouldn't work because a magnet powerful enough to repel something several hundred or thousand feet per second would also be powerful enough to draw it back down the barrel once it exited the gun and the opposite polarized side flipped around. The theory would work, but it would be far to complex to really use effectively.
Our third idea was to load the projectile in the middle of two rings of wire that would be charged and turned into electromagnets thus creating a magnetic current that passes through the rings and would carry a projectile on that current thus propelling it with some degree of speed. Well this idea was shot down by a Law of Physics whose name escaped me at the moment that states "that nature will always try to counter to current of an artificial electromagnet. Basically, the earth would force a current that opposite direction against the current leaving the forward ring thus slowing or potentially even stopping the projectile once it enters said ring. The effect would be like a washer on a rubber band bouncing back and forth across the midpoint of the band.
So our final idea was to actually construct the barrel of the weapon out of a superconducting wire coil that would create a current flowing all the way down the coil and out the tip once it is electrified. The same law from above would try to counter the effect but not to the same extent as the projectile has already traveled down a long barrel and built up speed rather than merely being pulled through a small wire ring. The slight countereffect can actually be countered in one of two ways. The first being a quick and calculated activation and deactivation of the magnetic field just long even to through the metal projectile. The second, and more effective way would be to use a magnet as the projectile. A magnet of opposite polarity would travel down the current much more quickly as it is both being carried and propelled and at the end when it breaches the barrel and the adverse field takes over, it will be unaffected since it is a polarized item in and of itself. Given some professional production, a computer controlled firing mechanism, and some form of intercooling to keep the wires from being destroyed, this gun would be capable of firing a projectile extremely quickly based on the power of the magnet (which can be increased with the use of capacitors) and make absolutely no noise with zero muzzle flash since there is no combustion.
We actually arrived at this conclusion without ever opening a book, clicking a website, or touching a magnet. This was all in our heads
Then we did some research and discovered someone actually had the same idea and built a small and ugly version that fires a big friggin rod of iron. The sound you're hearing isn't the weapon firing but rather the projectile hitting its target. At the end when he demonstrates the pistol, notice how accurate it is at close range and with relatively low power.
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
Last edited by Unorthodox_Z; 11-09-2006 at 01:32 PM.
Actually I saw an episode of future weapons on discovery with the same magentic propulsion idea. The gun can rip of a staggering number of rounds...I believe they were using for multiple applications, including on sniper guns (experiment only). Good thoughts though...
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Actually I saw an episode of future weapons on discovery with the same magentic propulsion idea. The gun can rip of a staggering number of rounds...I believe they were using for multiple applications, including on sniper guns (experiment only). Good thoughts though...
Was that the metal storm one? Metal Storm used stacked bullets and perfectly timed rapid jolts of electricity to ignite the bullets. It shot like 40,000 round a minute. Something crazy like that! I didn't see the magnet one but after my thought experiment I'd really like to.
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
This gun has a total power of almost 4 kilajoules. It shoots a finish nail at over 100 mph using 3 coils, runs at 450v. and was built on a budget so it only cost me like 500 bucks to make.
Now, the charger on that thing can go up to 1.2Kv, and it would be nice to charge some caps up that much, but to get much capacitance at that high a voltage is EXPENSIVE, and hard because only aluminum electrolytic caps do it, and they dont have a good margin of error in their capacitance. (like -20% to +80%). So it's hard to do your math right, cuz you dont really know exactly what you have, also the capacitance of the caps changes after several firings with those types of caps. Not only this, but calculating the actual force on the projectile is no simple task either, and then you have to remember that when you shut the power off to the coil, all the field in the coil has to go some where, so you normally get a HUGE voltage off the coil when you try to shut it off. Also, the magnetic field strength is dependant on the # of turns of your coil, which also chooses your resistance, and the amount of heat/current you get. However, if you use large wire you coil gets big and your basic field assumtions on standard coil equations no longer apply, so you cant use too large of wire, or you have to do a finite element analysis of your coil to really get good results. Also, switching is a BIG issue... how the hell to you switch on and off say.... 8 kila-amps? The one above uses SRC switches rated to 3Kamp, or 8Kamp for 8us, at 800V. They cost me 40 bucks a piece, there are 3. These are cheap, but when you turn them on, they dont shut off until the curent goes to 0, so you have to compleatly drain your caps before it will shut off, so you have to use an RLC calculation to set your time to shut the field off.... but how do you know when you need to do that when you cant really calculate the force on the projectile? As you said, you once the center of the projectile is in the center of the coil, you need to shut the field off or else you will try to suck it back in. But even then depending on the size of field you have, your resistance, and how fast you can bleed the field off the coil (but letting a reverse current flow happen) changes... so how do you know when to shut it off?... kinda trail and error. So, to help with this, you have to put a VERY large diode across the coil, so when you shut it off, you dont put out say... 10KV and blow up your SRC, instead all the current goes through the diode and saves your switches life, and helps get rid of the field faster. I used 1.2KV 800amp, 3kamp pulsed for 8us fast switching diodes (10 bucks a piece). But using an SRC is hard again as well, because you dont really know the capacitance of your caps, for above stated reason... so you're screwed... so the solution is to use a very high powered transistor to do the switching right? Well, yes you can do this, with an IGBT (isolated gate bypolar transistor), they make IGBT's that can handle over 10Ka at several thousand volts..... they only cost.... 5,000 USD a piece... So I wonder what the guy above is using for his switches.. hehe... I couldnt afford something like that, so I built the one above. But with IGBT's you could make a nice test setup to see exactly when it's best to turn the coil on/off... you could however make a feed back system that uses a small laser diode to measure when the projectile reaches the center of the coil and use it to turn the coil off, and that would be even better... Perhaps I will build one like that sometime soon..... not a cheap thing to build though... but that's why i have a job... hehe of course, the barrel material also makes a difference, I used a small brass tube, as I couldnt get the plastic I wanted, but using a plastic would increase the effeciency of the magnetic coupling.... so next time I'd use plastic. Also magnetic coupling changes with the length of the projectile, and it's best when the projectile is 1/2 the length of the coil, but that makes timing hard, as if you make a larger field it takes more time to break it down when you need too, and with a smaller projectile -> heigher speed, etc, etc need to shut it off faster. usually a projectile of equal length of the coil is used as it's a good compramise. Also, experimentation has shown that using more than 5 coils in a row does not add much, so usually only 3-5 are used, the 1st adding the majority of the power to the projectile (something like 75-80%).
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03 DB track with borla TD and pop charger: soon to come, 5/16 spacer, maybe mrev2. The greatest single cause of atheism today, is Christians, who acknowledge Jesus with their lips and walk out the door and deny Him by their lifestyle. That is what an unbelieving world simply finds unbelievable.
Last edited by shushikiary; 11-09-2006 at 01:56 PM.
We did actually bring up the the idea of what would happen when a field that strong was shut down. We were worried about potential arcing so since we hadn't tried a physical application yet, that went in our theoretical "to do" bin. We are very interested in building a working model. Lol, my friend is actually trying to get ASU involved for funding I don't suspect that'll happen anytime soon but that would be a lot of fun to work on perfecting something like that.
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
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I've made both (in a high school physics class haha, amazed we got away with that) a gauss cannon and a railgun. Personally I favored the rail gun. Spend enough on high conducting low friction materials and it is sweeet. Ours was alot more accurate then the gauss cannon as well, but perhaps that was simply design flaws.
Did I mention our proffessor built a trebuchet for that class too? Combine a (literally) nuclear physicist, a garage full of capacitors, wires, scrap metal and wood, and the fact that he was quiting at the end of the year and just hink of how much fun we had
I've made both (in a high school physics class haha, amazed we got away with that) a gauss cannon and a railgun. Personally I favored the rail gun. Spend enough on high conducting low friction materials and it is sweeet. Ours was alot more accurate then the gauss cannon as well, but perhaps that was simply design flaws.
Did I mention our proffessor built a trebuchet for that class too? Combine a (literally) nuclear physicist, a garage full of capacitors, wires, scrap metal and wood, and the fact that he was quiting at the end of the year and just hink of how much fun we had
Nice rig shush!
That's hilarious. What the hell did you guys do with a trebuchet?? Throw VW's?
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
LOL, thanks all. I am an electrical engineer after all.... above rig was a final project for my embeded systems class.. lol
yea those trebuchets are sweet! ever see the guy in england that spent 40k on one, and it throws cars/pianos, etc?
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03 DB track with borla TD and pop charger: soon to come, 5/16 spacer, maybe mrev2. The greatest single cause of atheism today, is Christians, who acknowledge Jesus with their lips and walk out the door and deny Him by their lifestyle. That is what an unbelieving world simply finds unbelievable.
God Damn guys... I am glad your on our side... Wait, you are on our side right..? I’m not sure what side that is really.... Never mind, I'm on whatever side your on.
Very impressive Shush, and UZ.. very well thought out. I know the Army has been looking into this technology for some time now.
But it is a lot easier to use a special silencer/deflector on the sniper rifle which absorbs deflect muzzle flash. Yes I know this affects the accuracy, but a well trained sniper can take this into account along with wind, thermal changes and trajectory drop.
God Damn guys... I am glad your on our side... Wait, you are on our side right..? I’m not sure what side that is really.... Never mind, I'm on whatever side your on.
Very impressive Shush, and UZ.. very well thought out. I know the Army has been looking into this technology for some time now.
But it is a lot easier to use a special silencer/deflector on the sniper rifle which absorbs deflect muzzle flash. Yes I know this affects the accuracy, but a well trained sniper can take this into account along with wind, thermal changes and trajectory drop.
Very true... for now Give us some time to refine!
__________________
---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
God Damn guys... I am glad your on our side... Wait, you are on our side right..? I’m not sure what side that is really.... Never mind, I'm on whatever side your on.
Very impressive Shush, and UZ.. very well thought out. I know the Army has been looking into this technology for some time now.
But it is a lot easier to use a special silencer/deflector on the sniper rifle which absorbs deflect muzzle flash. Yes I know this affects the accuracy, but a well trained sniper can take this into account along with wind, thermal changes and trajectory drop.
Damn right brent... and bullets are pretty cheap still
This is one of those threads that makes me realise the insane amount of talent that exists on this board alone. Props to you both.
Lol, thanks. Actually I was telling this same friend about this forum and how the majority of the people on it are actually relatively intelligent people not just punk ass kids like on some forums. Now we have our fair share of those too but I'd like to see the SRT4 guys build silent weapons of destruction!!!
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
That's hilarious. What the hell did you guys do with a trebuchet?? Throw VW's?
Nah, it was only about an 8ft arm, not a huge one. Tried sizes ranging from golf ball to basket ball, but the oranges and baseballs worked best. One went too far and splattered in a parking lot acroos the quad about 5 ft from a car. Thats when the dean came running out of the office. Our teacher just chuckled and said to hurry up if we wanted to fire it again
Nah, it was only about an 8ft arm, not a huge one. Tried sizes ranging from golf ball to basket ball, but the oranges and baseballs worked best. One went too far and splattered in a parking lot acroos the quad about 5 ft from a car. Thats when the dean came running out of the office. Our teacher just chuckled and said to hurry up if we wanted to fire it again
Lol, thats awesome! I wanna met that guy
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
With conventional weapons the load must be sub-sonic or else the bullet will break the sound barrier and you will get a loud supersonic crack. That puts a limit on you muzzle velocity and effective range.... Those limits would remain the same even with practically all non-conventional alternatives that involve projectiles. Firing a projectile in a quiet manner is not really the hard part... even conventionally... silencers are pretty simple devices and work well.... but a subsonic projectile isn't effective at sniping. Sometimes they will suppress a sniper rifle just to suppress the initial bang, and let the crack keep them guessing where it came from.
My idea would be an intensely focused microwave beam of some sort.... kind of like the microwave weapon they already have now that is used to disperse crowds...
With conventional weapons the load must be sub-sonic or else the bullet will break the sound barrier and you will get a loud supersonic crack. That puts a limit on you muzzle velocity and effective range.... Those limits would remain the same even with practically all non-conventional alternatives that involve projectiles. Firing a projectile in a quiet manner is not really the hard part... even conventionally... silencers are pretty simple devices and work well.... but a subsonic projectile isn't effective at sniping. Sometimes they will suppress a sniper rifle just to suppress the initial bang, and let the crack keep them guessing where it came from.
My idea would be an intensely focused microwave beam of some sort.... kind of like the microwave weapon they already have now that is used to disperse crowds...
I've seen those! That would be pretty awesome to burn a hole in your target from a mile away.
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---2006 Black Charger SRT-8. Corsa Cat-Back exhaust kit and Mopar CAI (searching for a good tune and underdrive kit). ---2004 Daytona Blue Z Coupe. JWT Popcharger, Borla True-Dual exhaust, and an Unorthodox Racing Underdrive kit.
Sweet Gauss Cannon (a.k.a. Coil Gun)
That's hilarious. What the hell did you guys do with a trebuchet?? Throw VW's?
