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Future Small Arms

  1. Nov 4, 2003 #1
    A couple of weeks ago on another forum (RPN), I brought up a couple flaws in the technology they were using in their role play world.

    But I get ahead of myself. RPN is a roleplay board that I visit fairly often, as I do have a penchant for RP, especially good RP. However my hatred of purely theoretical weaponry and technologies came to a head when the owner of the board proposed very high level electromagnetic weaponry (Read: railguns) for the application of SMALL ARMS.

    Now, as anyone who truly understands the working of a railgun and it's variants, I flipped a lid and went on for several posts about how such a thing is impossible, due to the fact that the size of the rails themselves directly dictate the maximum velocity of the slug. This is due to the fact that the magnetic charge on the rails and the magentic loop behind the slug itself which drives the slug to accelerate at one point become equal in charge. This means that the longer the barrel, the faster the slug (So long as certain energy requirements are met).

    But they actually have the gumption to say that UHV (High end railgun speeds, well over 10km a second) can be applied to PISTOLS when the maximum length of a railgun rail to achieve 10km a second would be around 10 meters, give or take about .5 of a meter.

    of course when I repeatedly bring up this fact they all jump on me using erroneous arguements based on emotions rather than facts.


    Then during a discussion with the owner he says that they don't use electromagnetic propulsion for their "railguns" but rather a system of gravitic propulsion. I'm not 100% sure what gravitic forces are, but I think they are one of two things.

    1. Manipulation of gravitons. It is my understanding that "gravitons" are theoretical at best.

    2. Manipulation of gravitic waves or somesuch nonsense.

    Again, I'm not sure what these "gravitic" forces are. Perhaps I could recieve some info on them? I tried looking them up multiple times but to no avail, which leads me to believe it is the work of bad sci-fi.

    Any rebuttal suggestions would be nice, and uh... sorry about the rant-like nature of this post.
  2. jcsd
  3. Nov 4, 2003 #2


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    When you're using magi-tech you can make it do whatever you want.
  4. Nov 5, 2003 #3
    Re: Re: Future Small Arms

    Sadly, this is true. I just wish they would admit their creations are SCIENCE FANTASY rather than science fiction.
  5. Nov 5, 2003 #4


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    I see no reason for any arbitrary limit on the muzzle velocity. If you assume they can have an arbitrarily large amount of power at their disposal, and perfectly superconducting magnets, what limits the muzzle velocity? I would think that recoil would be the biggest problem. You can make a recoilless rifle, but you can't make a recoilless rail gun without shooting something really wicked out the back.

  6. Nov 5, 2003 #5
    Problem with such is that in order for you to have a UHV weapon, the rail must be much bigger than a PISTOL would allow. You would need at least a heavy machinegun to reach UHV speeds. You see, the railsize actually directly dictates how fast the slug will go, and if it takes more than one meters to make the object go at the speeds they want it to, then they cannot use it for the application of pistols.

    Recoil was an issue too, but they countered that by having the rounds being suspended, even though there would STILL be a recoil. So they stated that they use "grvaitic waves" and various other treknobabble fantasy crap.

    Of course these are the same people that do not know what an oum value is
  7. Nov 5, 2003 #6
    I'm only vaguely familiar with the railgun concept.

    Would the rail have to be straight for its entire length, or could it be coiled or rifled in some way to gain length?
  8. Nov 6, 2003 #7
    Hmm, I had no interest in rail guns until I read your post. I think maybe Artman has a point. If the rail was bent into a spiral shape, a long length can be compacted into a small size. This is like making a capacitor for an electronic board.
    Also, the kickback could be dampened by firing two slugs one immediately after another so that as one slug is accelerated forward on one side of the spiral the other is being accerlerated backward on the other side. Also, the kickback is dependent on the mass of the slug. Really small slugs would be easier to control.
    Reaction force=F=ma=Mv
    What do you think?
    I too don't know what they mean by gravity waves and such. Gravity is suppose to everywhere ubiquitous.
  9. Nov 7, 2003 #8
    Very good point, I was trying to figure out how a railgun could be condensed, and I suppose a spiral pattern might work, however it could not be so condensed as to fit in the frame of a pistol.

    Of course the mechanics of such would be uh, to put it simply, difficult.

    It would be far cheaper to just use a straight rail system, but if you really need to reduce that rail size by about 75% (What I estimated to be the maximum you could "bend" the rail) the benefits of having that much space saved could far outweigh the costs of such.

    And now that I think of it, the two slug system might work, although it is grossly inefficient and would waste munitions. The average soldier fires a whole lot of ammo around during a single firefight, and to now double that number...woo boy, that'd complicate supply issues. Any system of dampening the recoil of a railgun is kind of inefficient actually, seeing as that most methods available would add weight, cost, and bulk to the weapon.

    And yeah, smaller slugs would of course have to be used, they are more materials efficient, easier to fire, and would require less energy to propel meaning smaller reactor/battery for the gun. Of course the 'tards at RPN are issuing 10mm slugs for assault rifles when 7.62mm slugs would be large and 5.56 would be standard. If I could adjust the rules myself I would state that 3mm is average for small arms, as that seems to be the most manageable caliber to use for such a system.

    Gravity waves or whatever, I have no idea. It is my understanding that "gravity waves" have been debunked as mere quackery. Perhaps someone could get some folks from the physics forum down here, they would most definately know.
  10. Dec 8, 2003 #9
    You cant make anything recoiless, you can only damp the recoil so it feels like its recoiless.

    [thinking out loud]
    As for the amount of rails. You could use nanotubes, there conductivity is amazing, there incredibly strong AND teher very very small. I dont know much about railgun physics though, or how they work.

    Doing some calculations just then, worked out from your previous statement of 10km a second with a 10m long railgun. One of the same diameter but only 20cm long would be able to propel something at 0.2 km/s. This doesnt seem too slow (assuming the speed doesnt multiply by factors depending upon the length of the tube) but its also not as fast as some, if not all bullets go. If you could pack 5x as many rails in there and improve efficiency over time (which is bound to happen as always does with technology) then i suppose the "potential" is greater than guns, but currently science fiction.
    [/thinking out loud]

    Maybe this has all been spoken rubbish, in which case im sorry :P

    I have never heard of them gravi things he went on about, looser :P
  11. Dec 8, 2003 #10


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    Recoiless armaments are common. They use a back-blast to counter the momentum of the projectile.

  12. Dec 8, 2003 #11
    The Nathan

    Railguns used by infantry are not at all impossible. The CEM at the University of Texas has already made some. Several years ago I saw a demonstration in which a soldier wearing a large backpack full of capacitors fired a railgun, embedding a slug about 6 inches deep in a block of hardened steel.


    Railguns are happening. The CEM is making railguns for use in a new type of tank for the USA military; these are due off the assembly line in 2014. Man-portable railguns are also happening. The last one I saw was 1.6 metres long.
  13. Dec 8, 2003 #12
    uh, do I understand correctly, that to accelerate something from 0m/s to 10km/sec in 10 meters would require 500,000 G acceleration? What kind of **** survives such Gs? 3gram bullet would require 15kN of thrust? Who can hold such weapon? Man-portable?
  14. Dec 8, 2003 #13


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    Ever fire a shotgun from your shoulder? Your hip? Firing from your shoulder, all the recoil goes straight into your shoulder. If you aren't standing right, it'll knock you over and if you fire enough rounds you'll get a bruise. Fire from the hip and you feel nothing. The first time I fired from the hip, I expected the shotgun to jump out of my hands and land behind me. But all you need is a few inches to absorb the energy. Its all about how the recoil is handled.

    That said, recoil cannot be completely eliminated without sending something in the other direction (not sure if gas recoil systems really absorb all of the recoil. The m-16 for example has a weight and a spring in the stock, but you still can't fire it on fully auto and hold it steady. Depending on the kinetic energy involved in a rail-gun, the recoil absorption system would need to be pretty hefty.
  15. Dec 10, 2003 #14
    Thats really what I had in mind. Can it be handheldable? I'm not sure if 3gram round is a "weapon". But with 50kg gun, 3gr round would make 30G recoil for 2ms. That would mean 0.6mm displacement and 0.6m/sec final v. Not much really. hmm.
    10gram round would on other hand create 500G recoil, and 50kg gun would displace 10cm with final v of 10m/sec which is already notable.
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