Inverse square law. The mag field will have a range of 1 projectile diameter. At 2 diameters you get 1/4 the force assuming no shielding. At 3 diameters it's down to 1/9. Plus the field will be focused on the projectile while it will be diffused elsewhere.

Given that all gauss weapons will use an electronic loading mechanism, you can have a significant distance between the magazine and the breech.

Umm, you are aware that prairie dogs are also "full of elastic tissue that simply snap back into place"?? It's just happens that the temporary cavity of a 3000 FPS round is larger than a prairie dog, so it blows apart when it exceeds the elastic limit. The faster the bullet, the larger the temporary cavity. Hence 1050 fps .22 LRs don't make prairie dogs explode while 3200 fps .223s do. That's a 2150 fps change that produces a rather spectacular effect.

I'll go out on a limb and predict that you get a pretty significant change in the temporary cavity with a 29,000 FPS velocity change... I really don't feel like playing with the math right now.

Plus, at a certain point (and several KPS is in the ballpark) you can start using the hypervelocity crater equation, which shows the size of the crater blown out by the energy release of the impact. I just don't feel like looking up the heat of fusion of muscle tissue right now.

Lastly, current research shows that some of the assumptions and previous research by Frackler (etc) about effects of the hydrostatic shock may be untrue. For example: http://arxiv.org/ftp/arxiv/papers/0808/0808.1443.pdf

1) And I'm quite sure that the 8-9 times magnification in base muzzle energy has nothing to do with this extreme disparity of effect between these loadings...

2) Not familiar but I seem to recall this being a ELE-type equation, IIRC. People aren't planets if this is the case.

3) Yes, it can lead to additional CNS effects but it usually doesn't. There are far too many shoulder wounds from full-on rifle rounds out there without any accompanying brain or spinal trauma to even come close to counting on this effect. Besides, the brain and circulatory system can take substantial fluctuations in both upper and lower pressures without damage. Hell, my blood pressure will spike 20 points on both sides if I pork out on salty stuff like pizza without any permanent effects, let alone the adrenaline surge if I'm scared by something or in danger.

The recoil of a weapon is based on the momentum of the round it fires. Momentum is VxM. So a 1 gram projectile moving at 5km/sec has a 5N momentum. So a 1 kg pistol would want to move at 5m/sec when you shoot it.

In comparison a 10mm auto firing a 11.7 gram bullet at 350 meters per second produces a momentum of 4N. Unloaded Glock 20 weights 785grams. So the Glock 20 wants to move at 5.2 meters per second.

Muzzle energy level of the 1gm round is 12,500 J. A 10mm auto round has a muzzle energy level of 716 J. So you get 17 times as much energy for a similar recoil.

(Yeah, it's really more complex that that, as I ignores the high velocity gases, etc. They actually increase the recoil of the glock and have no effect on the gauss pistol.)

And going from 3200 FPS to 32,000 FPS does what? Just a mere 100 times magnification is base muzzle energy. As I said (and you snipped) "I'll go out on a limb and predict that you get a pretty significant change in the temporary cavity with a 29,000 FPS velocity change..."

Actually, the "rails" won't be in contact with the projectile at all if it's designed correctly. Think of an in-line electric motor with the projectile being the coil.
As for the other bit, I suggest an experiment where you take a bowling ball and have it roll into a stationary solid weight of approximately 1/10th the size of the ball. You will see a substantial deviation and this effect will only be enhanced when firing a tiny object at higher velocity as it will have less mass (and not being round to just roll over it)to maintain it's trajectory despite it's obstruction. Now magnify this deviation by several magnitudes due to acceleration, the energy behind the effect being increased per-gram of the object, and the fact that with a small bore a deviation of even .05mm will cause the projectile to strike the precision rails at hyper-velocity as both the projectile and the rails are designed for long range accuracy.

Interesting argument but a cannon is a large tube designed to breech specifications well over the baseline destruction from a single loading to enhance it's longevity of use. Besides, you would need a large mass to effect the 50+ pound shells the same way a bit of dirt will effect a 1.6mm dart that weighs less than a gram. Also, the barrel obstruction isn't about the bullet deviating, it's about the chamber blowing up in the shooter's face. When you're just guiding a round that is basically sealed to a steel tube it's much easier to keep the trajectory despite debris (even though you will still see increased deviation) than with a free-floating projectile being guided by a series of stepped fields created by comparatively delicate electric apparatus.

Umm...velocity and muzzle energy with identical projectiles are not on a linear scale.

Sure. That's why 10 times the velocity produces 100 times the energy.

I use the term 'rail-gun' as a generic term for many sorts of gauss weapons. Some would involve a proectile traveling down a rail, some would not. There are merits to a variety of solutions.


In the first case your example is obviously inappropriate. We aren't talking a bowling ball striking a pin, where the difference in velocity and mass are minimal, we are talking about a hypersonic round striking a speck of dirt several moving at several orders of magnitude faster, massing several orders of magnitude more, and perhaps criticaly to you understanding, the difference in momentum is likely to be exactly the same as what you might see in a conventional firearm, the gauss round will simply be moving faster.

So what will happen will be no different then what happens in a rifle or cannon. A tiny speck of dirt (massing a hundreath of a gram) simply cannot impact with enough force to overule the other forces at play. A gauss round is still going to have a huge amount of momentum, comparatively, to the dirt. And the forces at work at keeping the round on the correct path are going to be just as strong, if not stronger in a rail-gun as they are in a conventional rifle. Those magentic forces and the reistance of the rail are not just forcing the round forward, they are also forcing it to be centered along the path.

If it helps your understanding consider that a stiff breeze blowing into the barrel could impact just as much momentum as a hypothetical grain of dirt. And after the projectile leaves these forces could have an effect on the bullets trajectory, perhapce even a dramatic one depending upon the exact forces and distances involved, but within the confines of the barrel the forces are entirely overwelmed by the other forces at bay.


1stly, the forces keeping a small dart in line are likely to be just as strong, if not stronger as those that go into the design of a cannon. 2ndly momentum is proportional to mass and velocity. A kzt pointed out a rail-gun may be designed to maximize energy for a given amount of momentum, in this case a hypothetical rail-gun round will be just as hard to deflect as a cannon round. As even though it may mass much less, its velocity gives it just as much momentum, and of course much more KE.

To be honest I'd be pretty nervous about anything in the barrel of something running at multi-km sec. The round hitting the debris is the same as the debris hitting it at the same velocity. There is a hell of a lot of potential energy that wants to convert itself into heat. I'd expect that this would, at worse, cause a serious malfunction of the weapon as there isn't going to be any chamber pressure spike. But I'd also expect that it would have built-in tools to prevent and detect issues like this.

The amount of energy expressed is going to be equal to the amount of energy the projectile loses due to this interaction. Given the negligible momentum of a microscopic speck of dirt, this isn't going to be a whole hell of a lot. Especially on a conventional rail-gun it likely to be entirely overshadowed by the frictional losses along the rails. Though you are right that, depending upon the velocities involved the dirt is likely to end up vaporized into a gas by compressive heating, and not blasted out the end of the barrel or something.

One thing is for certain though, rail-gun barrels are going to have to be extremely sturdy. They have to be just to withstand the stress of firing alone, much less any other forces that might enter the equation. Far from being a fragile device, a railgun armature is likely to end up the next best thing to indestructible.

The actual terminal ballistics of small ultra-high-velocity projectiles needs to be studied before anyone can make any sort of speculation about the usefulness of small rail guns. The two biggest issues I can see are fragmentation and overpenetration. On one hand, it is highly likely that the projectile will tear itself apart in its target. On the other, it is likely that a single human body will not be able to stop those fragments. The behavior of extremely fast moving small projectiles in flesh and flesh-like substances, as well as their maximum penetration, are going to be rather large factors in determining the practicality of such weapons. It is possible that such velocities will simply produce a projectile that is equally effective but substantially more dangerous to allies and bystanders.

It certainly would be useful. Based on just the micrometeor equation (no assumption of any AP design etc), the 1gm round moving a 5 km/sec would put a hole in >7cm of titanium.

How lethal is another question, but it certainly would be militarily useful.

Good points. I'm not trying to discuss some insane railgun that tosses tiny bits at insane speeds, myself. I'm trying to put forth the idea of a medium energy (about that of a modern 7.62mm NATO) infantry system that takes advantage of the default AP projectiles, superior ballistics, and smaller cross-section of railguns vs. conventional firearms. You get higher ammo capacity, simpler feeding systems for improved reliability, longer effective ranges, and similar terminal effect with the correct projectiles. Also, swapping your entire infantry weapon systems to batteries and standard 3-4mm fletchettes would be absolutely fantastic from a logistic standpoint without compromising battlefield reliability.

Except, as I pointed out earlier, simply having the smaller ammunition will not necessarily increase ammo capacity, as you must still take into account the space required for the energy cell to fire the ammunition. Gauss weaponry requires a huge amount of power to fire, so I strongly suspect that even when the technology is small enough to use in such weapons, the vast majority of the magazine will not actually be containing ammunition, but rather batteries.

Batteries are sold seperately
no,Really
1 Slot for the 10 Shot magazine and 1 for the Battery ( 10 PP)
or via cable to a 30 PP Pack or 80 PP Backpack

Hough !
Medicineman

They are really pretty spiffy on an AFV. The engine of a tank can easily drive a megawatt sized generator. Use an ultracap system recharged by the engine when the vehicle isn't moving full out... Then you only have to worry about ammo.

and thats when one stop at a hardware store to grab some 9 inch nails

So they can have whole buckets full of non-spec, almost impossible to feed reliably, soft steel projectiles that won't be worth a damn passed 100m or so?

So, random sidenote: I'm slightly confused by the fact that a thread about gauss weapons has run to five pages, and as far as I can tell not one poster has suggested their ridiculously over-the-top stats for Reason yet. And in a forum for a cyberpunk game, no less.

There's just something darn peculiar about that.

well it was meantioned once. But no stats. FA guass rilfe with minigun rules sound good? 250round belts.

Ask for a talking pony while you are at it.

A 30% smaller projectile diameter is a 50% reduction in mass, more when the bullet gets shorter. You either go to dense exotic materials (depleted uranium) or get to high velocities (sabot).

Otherwise everyone would use .17 HMR. It too has a flat trajectory, assault rifle velocity, and comes in a small ruck-friendly package.

People don't use it because its ineffective at stopping game larger than "varmint" with confidence, let alone a soldier with battle rattle.

If you want an M16 with a 300 round magazine holding 1.2kg of 5.56 slugs that fires them elecromagnetically at the same speed as a NATO cartridge, just spend 1800J per shot from a backpack powercell and you can do it. Just don't go too far off grid.

But to get an armor-busting gauss weapon you have to go very high velocity, meaning very energy hungry. And no matter how you slice it, projectile weight has to drop to get survivable recoil at high velocities.

Ask for a talking pony while you are at it.

A 30% smaller projectile diameter is a 50% reduction in mass, more when the bullet gets shorter. You either go to dense exotic materials (depleted uranium) or get to high velocities (sabot).

Otherwise everyone would use .17 HMR. It too has a flat trajectory, assault rifle velocity, and comes in a small ruck-friendly package.

People don't use it because its ineffective at stopping game larger than "varmint" with confidence, let alone a soldier with battle rattle.

If you want an M16 with a 300 round magazine holding 1.2kg of 5.56 slugs that fires them elecromagnetically at the same speed as a NATO cartridge, just spend 1800J per shot from a backpack powercell and you can do it. Just don't go too far off grid.

But to get an armor-busting gauss weapon you have to go very high velocity, meaning very energy hungry. And no matter how you slice it, projectile weight has to drop to get survivable recoil at high velocities.

Yup, it's pointless to spend a fortune to recreate a 7.62mm rifle (that requires and endless stream of batteries) when you can buy a perfectly good 7.62mm rifle (where every round includes the propellant) today.

What gauss weapons primarily offer is obscene velocities, to not make use of this is crazy. It's like limiting your rifle design so it doesn't make arbalest obsolete.

IIRC, there was once a study that suggested 20N was about the max recoil for a usable infantry battle rifle. Somewhere between 3-5N is the reasonable max for a service pistol. Support weapons are a whole other kettle of fish. A 25MM auto-cannon firing full auto has obscene recoil, but it's damped by the mount and the 20 tons of vehicle it's mounted to.

Maybe, but on the other hand it is not inconceivable for battery technology, combined with advances in rail gun efficiency, to out pace the energy density of conventional propellants, even for hand weapons. At which point gauss weaponry would have some clear logistical advantages, as not only would the projectile part of the round be light weight, and thus easy to distribute. And refilling the propellant portion, the battery, would be as easy as plugging into a generator, which will be ubquitious on future battlefields (every motor vehicle will have one). However it is likely that some of this potential advantage in energy density will be spent in powering higher energy rounds instead.

Also, as kzt points out, for motor vehicles the logistical advantages are likely to become apparent even sooner. As I have said previously, Gasoline is a fantasticaly dense energy store, and the gas-turbines on tanks, helicopters, and jets are fairly efficent heat engines (30%+). All that is needed then is some excess energy capacity, and then capacitors to store this energy in. Then these vehicles could see a huge logistical advantage in mounting gauss weaponry.

I was thinking a 4x40mm finned dart, actually. Make it a mix of plastics and tungsten powder (or maybe the super-fly stuff of those special AP/frangible loads I saw on Future Weapons) with an aluminum/copper coil also inside for projection. Default APDS-type effect for -4 AP added to typical 6P (But I would call it 7P) AP -2 of a 7.62mm NATO-type loading and it'll do just skippy, thanks. 6-7P and AP -6 for the final damage stats.
I figure about a 5.5g projectile with 4000J or so behind it for around 1200 m/sec. Nice long accelerator for accuracy, smartlinked, bipod front, unipod rear, and 10-20 round magazine. Great sniper weapon with minimal recoil when compared to a standard rifle of the same type, easy and fast follow-up shots, no muzzle flash, and only the noise of the round breaking the sound barrier if you're close to in-line with the shot. Adding 10-20% to each category of the Sniper Rifle range chart in the BBB would make it worth lugging around, I think.

You mean just like a 6mm Remington? Wow, seems like a lot of work to produce a gun that fires a round that nobody uses for sniping.

What you really want is a weapon that can throw a VERY small (1mm or less) diameter projectile at a respectable percentage of light speed, say .1C or so. Then the hydrostatic shock would be violent enough to actually make someone explode with enough force to damage everyone within 2-3 meters. But, as mentioned before, the recoil and power consumption would be horrendous. Even a troll in assault armor with maximum strength upgrades would be unlikely to be able to fire it safely. Might make a good crew-served weapon though if you put it on a vehicle (say, an APC, IFV, or MBT maybe) or a LARGE tripod (about the size of a swingset only MUCH heavier) that's bolted down. But, if you're gonna do that you might s well use a larger projectile moving at much slower speeds. Then there is the problem of melting your projectiles. About the only thing that could resist that kind of friction is probably pure carbon. But hey, that's just my .02 .

Does that .1C mean 1/10 of light's speed (what was? 300'000 km/sec.?)?
Well considering that cinetic energy (if the bullet is considered a single point placed in its center of mass) is equal to 1/2*M*V² whit "M" being the mass os the bullet and "V" the speed of said mass (V = 0,1C = 30'000'000 m/sec -> V² = 900'000'000'000'000 m²/sec²) it is safe to say that the energy needed to fire the thing is outstanding, just to use an understatement, also it takes time (and so barrel lenght) to acccellerate the fragging (micro)crowbar, which means that unless you use a monstruously powerfull discharge (at which point I might ask how is the system gonna withstand that peak) you are going to need a considerably long barrel (either in the order of 10⁴ m or above), so you are going to need several (futuristic high output) powerplant. It would be fun to see the thing built and than the brainiacs realize that its too big to be fired (fucking earth curvature, weren't for it we might hit something instead of shooting into the space), also wouldn't the friction with the atmosphere cause the bullet to burn?
A much bigger version could be usefull as a launch devices for spaceship directed toward another star-system, that is if you don't consider the death of the passegers due the accelleration (blood vessel are going to rapture everywhere) a drawback.

Man can't I just take a joke for what it is and avoid trying to rationalize everything?

No, I'm quite certain that I didn't mean a round with 3/4 the muzzle energy, 10% less muzzle velocity, and far inferior long-range ballistics. Thanks for double checking though.

I see the purpose of an infantry railgun to be the default AP projectiles, the superior long range ballistics, and the lack of muzzle flash and/or the noise of the muzzle gasses. I fail to see where tossing Brad nails from car-sized accelerators to take out tanks is the only possible application of this technology.

The problem with using intermediate velocities like that is that they are achievable with gunpowder. 1200 mps is doable with gunpowder, even 2000 mps is doable from tank guns. So why don't people use bullets like these?

Well, for one reason, light bullets drift like mad in wind. But wait, it gets better. If you are using essentially a LRP from a railgun you have to use fin stabilization, as I haven't seen anyone suggest how you produce spin in a railgun. Plus LRPs are not typically spin stabilized, as spin decreases penetration and isn't terribly effective on long (length over 5 times diameter) projectiles anyhow. So you have a light, fairly slow moving long finned projectile in a crosswind. Hmmm, sounds like a weathervane to me.... I have my doubts as to how effective a long range round like this going to be, or how effective at penetration a round that hits yawed by 10 degrees will be.

To reduce the muzzle flash and sound I'd suggest using suppressors.

Unless you are going to get performance you can't get from gunpowder I'd suggest using gunpowder. You really need to be into the >2km/sec range to make all the limitations make sense, unless you assume some sort of arbitrarily high essentially free energy storage density.

No, I'm glad you did. It saves me from making a long rambling post about while I love railguns, that kind of energy is rediculous. A 1g projectile moving 3e7m/s (.1c) has like 450GJ of energy, or about 100MT of TNT. Obviously no battery (or any chemical energy system) could contain this amount of energy in a man, or vehicle portable store. And you are also correct that accelerating it up to these velocities in a reasonable length tube is also completely impossible.

However on the bright side, the make up of the projectile would be completely irrelevant at these sorts of velocities.

True that. At those speeds, you're no longer talking about railguns; you're talking about particle accelerators. I don't think SR's got up to PPC technology yet...

Meson guns and APAWS. Fun times.

I think someone was quoting Ringo's Posleen/Aldenata books. Those are antimatter-powered, meaning each one is accelerated thanks to a small nuclear detonation. There the projectiles ionize the air leaving a lightning-like arcand rounds punch through a half-dozen horse-sized aliens, each of which explode from the fluids in their bodies spontaneously converting to gas.

I have been thinking about the plausible high speed (>1.5km/s) projectiles where the round exceeds the speed of sound in water, aka the human body. That means the shockwaves passing through the tissue will be as fast as a shockwave can pass through the body. The Doppler effect will result in the exit wound being struck by high frequency shockwaves. That is going to cause some ugly wounds as the body experiences something analagous to detcord inserted through the body and then detonated. It won't blow the person up but it's going to do some horribly weird things along the wound track and to air pockets within the body in the range of the shockwaves (lungs, digestive tract, joints, etc) as if they were caught in an explosion.

The whole posleen stuff was extensively argued on baen's forum. The round actually destroyed itself on the first horse, and further damage was done by fragments of the posleen. For what they really wanted the ROF was far too high and the MV far too high. 600 RPM and .50 cal round at maybe 2km/sec would have worked far better, as that round would have penetrated through multiple ranks and wouldn't have resulted in each target eating 30-50 rounds. Of course, the weapons were designed by people who either had no clue or actively wanted the humans to all die gloriously.

This was also the series with the terawatt laser support weapon, which Ringo (after he realized what he had done) promptly refused to ever talk about until the last book where it destroyed a huge swath of ultrahard targets before it destabilized. I'd have installed it in a remote rig myself...

Well, I guess there is nothing stopping you from going a bit bonkers and going for .50 BMG energies at 2700 m/sec or so with the same projectile. That much speed, a bit of spin won't make enough difference to matter on the penetration side of things for reasonable targets. Less than one second of travel to record-breaking shots certainly wouldn't hurt any marksman feelers, IMO.

The posleen presented either ultra-hard or soft targets. There wasn't much where you could make use of the AP capabilities you could get in a man-carried weapon, or even a powered armor carried weapon. Other then his insane terawatt laser, 16" cannon firing delayed impact fuzed nukes were how the humans generally defeated the hard targets.

Two points:

Thus far, on the topic of dirt in teh barrel I've seen a lot of waiving it away as 'microscopic'. In my job I've had to handle rifles who had exploded in the face of shooters from a single (yes, a SINGLE) grain of sand in the barrel. I have a hard time reconciling how merely upping the velocity of the round (while, in many examples thus far decreasing it's diameter...) would prevent that within the limits of existing, and postulated, materials technology. Unless the barrel obstruction is less than the gap between the round and the magnets (or is squishy enough to get pushed through said gap...) it will present a significant mechanical problem to the rounds passage.

Secondly, only one person has mentioned this, but the length of the rounds being fired is a matter of some debate, and has a strong influence on things like mass and so forth. Modern pistols use roughly a 2:1 ratio round (twice as long as wide), rifles a 3:1, and MOST theoretical gauss weapons I've read about seem to work closer to 10:1 ratio... though I am aware of at least one fictional example of 'dinner plates of death' (1:1 ratio, but with caveats that the thickness is not equal to the diameter).

Oddly, the entire debate seems to have shifted to debating the merits and values of Gauss (rail) smallarms, when all shadowrun put out was a gauss Heavy Weapon. The question should not necessarily be how well it performs as a killer of men but as a killer of materials, light skinned vehicles OR alternatively its effectiveness at suppressive fire operations or other support anti-infantry roles (machine guns and mortars vs. AMRs)

In the examples present, the dust and dirt that could potentially jam the barrel, must be, if not microscopic, at least very small. If we are talking about a 1mm barrel (not saying we should be, just giving an example) obviously the largest any dirt particle would be 1mm then. The mass of a 1mm^3 particle of dirt is tiny, like 2mg, or 3 hundredths of a grain. The ability this particle has is proportional to its momentum, and thus its mass, and is thus very small. Even in comparison to a needle like 1mm round. It is also important to realize that while a rail-gun round may mass much less, it may carry just as much momentum as a conventional round. Momentum is proportional to both mass and velocity. A rail gun will typically fire a less massive round, much faster, as this is both more efficient for it, and keeps the recoil at a manageable level.

So what is going to happen to the bullet and the grain of dirt? Well given the nature of dirt and the velocities involved we can expect an inelastic collision, which will mean the much the dirt will end up deformed and potentially vaporized (depending upon the velocity involved) with the remaining mass ejected out the end of the barrel at the same velocity as the bullet. A small amount of KE will be lost, but not much. It is also possible that the bullet will be deflected slightly, but not much, as the forces accelerating the bullet forward are not only pushing it forward, but also acting in lateral opposition to one another, keeping the round centered.

Now could you if you wanted to destroy the barrel of a rail-gun by putting debrie in it? Sure! I imagine if you pored some molten lead down there or had a squib load you would get the effect you want. But in terms of dirt a rail-gun will likely end up no more vulnerable to dirt obstructions then a rifle or any other firearm would be. Since the momentum and physics involved in these collisions are not that different.

As for a single grain of dirt destroying a rifle barrel, I find that highly unlikely and contrary to my experience with firearms. Most firearms end up with much more debris and fouling in their rifling from simple use then a single grain of sand could cause. I have seen some people on the range fire some VERY dirty firearms with no ill effect.


There is no specific reason why railgun rounds need be any particular shape (or diameter for that matter). However, without rifling a long and thin shape tends to produce the best aerodynamic results, and it has benifits in terms of armor penetration. But there may be merits to other shapes.


I see no reason to limit the debate! If you can get the efficiency of rail-guns up high enough and the energy density of batteries up high enough, they could have applications in all sizes. Rail guns do get more efficient at lower momentum, and less massive rounds are the only way (regardless of means of delivery) to deploy higher KE rounds without breaking a shooters wrist. However, neither of these demands a railgun be designed to deliver tiny death slivers. In fact as the effective energy density of railguns rises and potentially surpasses that of conventional firearms, I would expect to see them replace firearms even if designed in the same mold (KE, caliber, and what not). Due to the potential logistical advantage.

Oo! I wanna custom rail pistol for my teenie bopper character! It fires heart-shaped slugs at 6x the speed of sound! Can I mr. GM? Pweeease?

Gauss Pistols?
Don't railguns need a certain lenght to accellerate the bullet to the disired speed?

While longer barrels certainly makes it easier, it is not strictly necessary.

Than you are going to need a truck of peak discharge batteries to relise all that power at the same time, praying that the gun doesn't blow up; seriously if you reduce the lenght of the barrel by half you are going to pump twice the original power per time unit, how muck is going to be the lenght of the barrel of an heavy pistol compared to the gauss rifle?

The rate at which the projectile is accelerated, and thus the rate at which the power is released is entirely unrelated to the mass or volume storage of that amount of energy will take. Gauss weapons release their energy so quickly that the time difference a few tens of inches in barrel length make is largely irrelevant. For practialy every sort of design the entire sum of that energy must be stored before the weapon is fired.

So the only real limitation then is how strong you can make your magnets, how much energy they can withstand, and how fast you can accelerate your projectile with out destroying it. Now, there are limits to these issues, but in practice you can generate pretty extreme acceleration in very short distances.

Quite right. My entire point in that post is that even at SRs 2070 tech level the idea is kind of ridiculous. I thought the reference to light speed would get that across.



Yup. People usually laugh like it's funny when I mention the number of revolvers I've had to replace cylinders on after they 'violently disassembled' themselves due just to lead smearing/buildup at the base of the barrel.

gauss rifles could detect foreign objects as either reductions in arc resistance (rail gun) or inertial resistance to the mag field (coil gun). should be Given the low mass of random foreign particles, the weapons should be able to clear themselves with low-energy "blank" firing.

I'm not sure the rail gun even requires it, since the projectile is contained in an electrical field that would also propel (or incinerate) any foreign matter.

What about recoil?

F=MV. Doesn't mater how fast it accelerates, just how fast it is going total. Typically the round will exit the barrel well before the shooter will feel the recoil.