And here I thought you were going to link this.

any object going around 4 faster that the speed of sound will cause compression heating the effect seen on reentering space craft. The higher the objects speed the more pronounced the effect will be.

and the obligatory link when talking about high speed objects and there effects: http://web.mit.edu/jcb/humor/high-speed-ravioli

Extremely fun read.

Umm...four times the speed of sound? That be some wussy shit! Tests as of the early 1990s were projecting these things at 10+ kilometers per second! If it was over 4.5 km/sec or so the projectile would ignite (as shown in the second video) from atmospheric friction.

Please also note that the video weapon is about 100 times (if not much, much more) as powerful as a man-portable railgun, was firing a projectile with a ballistic coefficient best described as "I like pie!", and would be designed to take such things into account because a sniper that belches a giant fireball whenever his rifle is discharged is probably a dead sniper in short order.

I don't know about that. If I saw a fire-breathing sniper, I'd probably run screaming.

Yeah, like the panther cannon, the gauss rifle is not a sniper weapon, which is probably why they're in the same category. However, it would be cool to see actual rifle and pistol class gauss weapons (a la Fallout 2). They could take advantage of the quieter action of a railgun, and fire a solid armor piercing slug for better penetration, but they wouldn't need to shoot at such fiendish velocities as to shatter all the nearby windows and send the HRT scrambling

Gauss Pistol [Heavy Pistol]
5P
-2AP*
SS
-
10 ( c ) + Energy
N/A
8,000
* Half armor before applying armor penetration.

Designed by Nicholas Rhys (my character - 10 Logic / 10 Armorer / 6 Hardware), the Gauss Pistol is the first hand-held Gauss weapon system. The weapon combines the armor-penetrating force of rail weapons with the portability of heavy pistols. The weapon takes an energy cell to power its magnetic accelerators (same as those used by the Ares laser weapons), in addition to its ammunition clip. Each shot consumes 1 point of energy; each clip has enough power to fire the weapons 10 shots.

The weapon uses specialized ammunition costing 200 per 10 rounds. The weapon is not available on the market, & must be obtained through Mr. Rhys.



My GM, for the last game, decided to use a random chart for (additional) starting equipment for each character (I did not like the idea, but whatever). This character ended up with 1 million Nuyen, to be spent as I desired with no limits on availability. As an explanation for how I obtained this, apparently I designed & sold a pistol to one of the worlds richest men. A few weeks later, this is what I came up with, & have been using ever since.

You should have made it a semi-automatic

meh, go FA

nah, go FA with the minigun rules, and up the ammo capacity

Gatteling Gauss weaponary for the win bar the fact that it would need a power plant to fire.

Also the pistol should be 6p

or maybe a couple of power backpacks

for a few rounds of fire. I lugged 100+of of power packs for less then 9 seconds of fire.

If you want to take advantage of the potential* of gauss weapons in a pistol, namely insanely high velocities that no propellant can achieve, with the muzzle energies a person can tolerate, that means a tiny little projectile at really high speeds. 700J (.45 +P muzzle energy) is enough to send a 1g penetrator out at nearly 1200m/s, aka Mach 3.5, which is roughly 3x the speed of a .357 slug and (assuming a .15 caliber round) with around 5x the penetration.

IMO that would be a Dam 3 AP -4 (after halving armor) firing what amounts to a dense BB. It causes a relatively small wound but it punches through virtually any armor. You can shoot up a vehicle but you've got to be a good shot to find something vital. I'd also say that it can hold far more rounds than the battery pack can power, 50 wouldn't be unreasonable for a ~ .16 caliber projectile with no propellant.

It should also use SMG range rather than pistol thanks to the incredibly flat ballistic profile.

*the other advantages of gauss weapons are the ability to store 50x as many projectiles as normal, rely on an electrical power plant, over specialized propellant, and have immense range thanks to the high velocities. The navy is the biggest gauss weapon investor because they have big electrical power plants (aircraft carriers are nuclear powerplants), space is at a premium on ships, and the bigger the engagement range the better. Oh, and a railgun could be used as an anti-aircraft weapon even against high altitude bombers.

SA would probably be to powerful (sure you can get this with modifications - I always do, but it takes up Slots). 6P would mean it at least equals heavy revolvers (AP -5 or greater, vs. -6 of APDS Super Warhawk).

I don't specialize in the field, so was looking primarily at balance & attractiveness when designing the pistol. I would think that you could sacrifice some of the velocity, & thus armor penetration, for increased round size & damage - hence the 5P -2 instead of 3-4P -4. Also, after taking into account the space required for the energy clip in a pistol sized weapon, there isn't much room left for the ammunition. If its actual slugs (opposed to BB's), it isn't going to fit much. I went with 10 to coincide with the energy clips.

Please note that in 60 years we'll have the technology to get something roughly this powerful easily to more handheld sizes. Imagine computers alone. Not too long ago (I think like 60 years) they were the size of whole rooms; now you can swallow them. Same thing with airplanes. Just over a hundred years ago we had the Wright Brothers' flight, and now we have super-jetliners, luxury jumbo jets, and airplanes that go to the moon.

I think that since they have a trailer-sized railgun now, in 60 years (probably much sooner) they'll have a man-portable one. And think, this is what was just de-classified. What about the classified stuff?

Corrected for you. Computers did not exist 60 years ago, & the ones 30 years ago (that used entire rooms) where roughly the equivalent of a modern calculator.

60 years ago would be 1948. There were effectively the equivalent of modern computers, in terms of being programable stored program machines, subject to the equivalence class of Turing machines, developed for / late in WWII, i.e. 1945. They were indeed physically monsterous, ate power, and broke often. The number of vacuum tubes needed was simply astounding.

By 1978 (30 years ago) we had hand held calculators able to do a full range of engineering calculations. While the Cray Supercomputer was pretty large, and the high end IBM of the time was substantial, there were many quite programmable, quite versatile, much smaller computers available. The Dec System 20 (based on the older 10 series hardware, and OS work done by MIT) was a thing of beauty. Even with disk packs, tape drives, etc, it still only consumed a small room. And the PDP 11, for example, could be kept in the same office with the people using it.

You can define computer in some narrow sense to change these definitions. But the definitions used by professionals, including historians, easily cover the 30 and 60 year old dates cited.

Yours,
Joel

My timeline could be off a bit, but punchcards were used during the 70's - 30 to 40 years ago. Before that, computers did not exist; their predecessors where no more computers than a monkey is human.

http://en.wikipedia.org/wiki/Computer_history

enjoy...

and the principle problem with handheld, or even man portable, energy weapons will be energy storage.

battery related tech do not develop at the same rate as computer tech, not even 1/10 of it...

i suspect thermodynamics has a very big say in that...
http://en.wikipedia.org/wiki/Thermodynamics

unless we can come up with some kind of superconducting capacitor or similar, it will continue to be a problem...

Well we have made kilofarad capasiters even if they are expensive. So I guess that in a few years this tech wount be far off.

It stands a reason for humanity hating the phisics, they burst our dreams like boubles.
There is also some problems with energy sources, energy storage covers bringing the power around but it must beforehand somehow and we aready have power-related problems today (just think how energy consumption is bound to grow in the future).

I didn't know of said capacitors.
You made me happy, it gives me hope for our future.

I would not be so sure. It is easy to overestimate the energy density of gunpowder (which is not that great) and the efficiency of modern firearms, which is only so-so. The most powerful gunpowders only hit about 5MJ/kg, with most performing well under that. And most firearms convert that into ballistic energy relatively poorly, at about 30% or so for the best cartridges. Which gives them an effective performance of about 1.5MJ/kg (and that is actually a pretty optimistic estimate).

Those levels of energy density are not entirely unachievable for batteries. The very best batteries on the market (Zinc Air) can do a little better then 1MJ/kg and some of the high-tech ones on the drawing board can do as well as 2.5kJ/kg. Combine this with a higher efficiency you might be able to expect from a railgun (batteries are VERY efficiency, above 90%) of say 50%, and boom. You have gauss weapon that can meet the efficiencies off gunpowder. Scale the battery tech up some more (another doubling is not unreasonable) and it will become considerably superior to gunpowder.

Note that all this is much worse than say gasoline which has an energy density of ~45MJ/kg (if the oxygen is not included). Which shows why electric cars have such a hard time competing against them, but also demonstrates why applying these difficulties to comparisons with firearms is inappropriate. Firearms are not nearly as efficient or energy dense as cars.

What about HollowPoint Ammo for Gauss Rifle ?
Would this be possible ?
Would it still be +1 DV / AP+2 ?

HokaHey
Medicineman

theoretically, it should be possible, just as APDS should be possible or however those bullets with the needle core and the lead casing are called

The bullets from an M-16 are exiting the muzzle at close to Mach 3.

There are some other issues to consider. It doesn't matter if you can get a battery that holds enough energy. You need one that can discharge enough current and reliably do so over a period of time. A battery that can put out enough amps to power a rail gun can put out enough amps to kill a man just by zapping him. You're also forgetting electrical resistance, which will result in a significant amount of energy loss, as well as the fact that not all of the magnetic energy will go into propelling the projectile; much of it will push at the rails.
But the biggest detriment to the man-portable rail gun is the rails themselves. Electrical resistance will cause them to heat up to very high temperatures, while the projectile will rub on them, tearing off pieces as it goes. A not-insignificant amount of rail material will be thrown out of the weapon as superheated plasma when it is fired. There are also powerful magnetic forces pushing on them, which are likely to cause warping. After repeated firings, the wear and stress on the rails will render the weapon inoperable, or dangerous to the user.

i just had a thought, isnt the slivergun a handheld railgun?

No.

that's more like the battletech needler weapons . . or an fully automatic shotgun pistol sized with shots as only ammo . .

The computer where make in the 1930's in america,england and germany. The closest one to than computer was make by than germany electric engeering. They where not called computer back then but where automattric calurateing machine. The world computer was coin in the late 1950's and early 1960's and for awhile both term where use. Automatric calurateing machine is the same as than computer.

It take 745 watts/sec of electric energy to equall one horsepower . It will take 223.5 kilowatts/sec to power than 300 horsepower engine. There was than all electric power car that was advestise able to reach 85 mile/hour of speed. In the find print it will only have than enought energy to last 30 minutes before you must total recharge the battery which can take afew hours. I have than book on submarines of the world. They use lead acid wet cell over more powerful dry cell as you cannot back then recharge dry cell but can recharge wet cell.

True enough, but this isn't necessarily a show stopper. First off there are battery types that can discharge energy about as quickly as you could wish. In the SR setting high-temperature superconducting loops are a possible solution. But for batteries that don't discharge quite quickly enough they can be fed by capacitors which are re-charged between shots. Current Lithium Ion batteries can discharge their energy very quickly if designed to do so, but probably not fast enough to power a rail-gun. They could quite easily recharge a capacitor between shots especially if they were (as they are in current SR rules) only asked to do it every 3 seconds or so. Indeed, a large array of batteries (like what you would need to power multiple shots anyways) could do this quite easily.


Possibly true (it would depend on the amperage and what not), but the same is true of any dense energy store. If all the gunpowder in your gun went off at once things would probably not be good for you. Or if all the gasoline exploded in your car. As far as safety goes, the most volitile batteries still have a leg-up on most explosive or chemical energy stores.


I am not forgetting any of these issues, but you may be overstating them somewhat. Yes of course there are inefficiencies present in a rail-gun, but they are likely to pale in comparison to those of a conventional weapon of similar power. A correctly designed rail-gun armature will avoid these issues. Not easily or without some effort mind you, but I don't believe the issues you raise are fundamentally show stoppers to the railgun concept, just challenges to be overcome. It is also worth noting that many of the issues are similar to those a more conventional firearm might face if it was throwing projectiles at similar velocities.

Indeed it is telling that already at this primitive stage of development railgun efficiency are about on par with those of fire-arms, about 30%, despite all the problems you site, with electrical reistance across the projectile (and thus projectile heating) and barrel friction being chief among them.

Did you not read the part of my post where I pointed out that gasoline powered cars make terrible comparisons in this case? Gasoline is a vastly more dense energy store than either batteries or the explosives used in firearms, primarily because the weight of its oxidiser comes free from our atmosphere and does not have to be accounted for.

When you compare the chemical energies of batteries to that of firearms the gap is not nearly so wide. And advances in battery tech combined with the potentially higher efficiencies of a rail-gun could potentially close this gap.

When gas reach over 4 dollar a gallon all the talk heads where asking why wasnot every one use electric car. I did study chemicisty many year ago.

i suspect gridguide and some kind of taxi/rent system for vehicles will be the way to do things...

basically something like trams, but with everyone able to order their personal one as needed...

That is one of the best parts of good future RPGs. All the nifty advances we expect (like efficient electrical cars, that don't have to be recharged when driving on the grid) combined with our Hot Rods that still use gasoline.

Except for the fact that firearms propellant energies are designed that way. The reason why every firearm doesn't use a mil-spec, stable explosive as the propellant is because the chamber pressures would make them very unwieldy and all but impossible to manufacture in a cost-effective manner. Imagine how much a firearm would suck to fire if 90% of it's weight was centered around the chamber to contain the explosive forces used to propel the projectile and 100% of the energy impulsed into your body at 100 times the rate it does now.

And it's the batteries that slow us down, in all honesty. We have electric motors that are much more efficient in weight and power than gasoline motors but our battery tech is so ass that it's impractical to make all-electric cars except as BS short-hop commuter tricycles with shells. I feel that the next big step will be hot (formerly referred to as room-temperature) superconductors. Once you get a medium that can store, discharge, and recharge almost instantaneously with high efficiency, you get to the point where energy weapons are practical. Anything else is a perversion of physics powered by insane powerplants for an effect you can get elsewhere for a cost that is only acceptable if that other source is a $1 million each cruise missile.

There's no advantage to using a larger, slower round and a lot of reasons why not. If you don't have the extremely high velocities with the requisite small round then you don't get the extremely high penetration (Energy divided by bullet cross section area). Pistol ammo is has the muzzle energy it does because shooters can't tolerate any more. Otherwise everyone would be using .44 automags or the horrifying BFR series of pistols. The gauss weapon provides a way to get armor-penetrating velocities with a pistol-class barrel and tolerable recoil. So ~700J is the muzzle energy limit for pistols, regardless of propulsion technique.

Oh and M16 ammo has a velocity of 940m/s, or Mach 2.75, and uses a .223 4gram round. I suggested a 0.16 1gram round at Mach 3.5. That gives a gauss pistol with more penetration than a M16 and less damage but with the same overall recoil as a .45 using +P ammo.

Second, the Thunderstruck is a gauss weapon, not specifically a rail gun. Rail guns are one form of gauss weapon but not the only one. The other kind is a coil gun. It's a series of circular electromagnets that switch polarities as needed to push/pull the round, like an advanced solenoid mechanism. Coil guns are harder to build because they require high speed computer controllers, something the SR-verse has in spades. The round is completely supported by the mag field so it's launched under very low friction and there's none of the energy arc of a rail gun.

This is true to an extent. It is certainly true that firearms cartridges (in handguns at least) at often artificial constrained in their power to reduce the forces they create to something a human can handle, or even just to make them more weildable. It is not true that this is the case for all firearms. Firearms not intended to be wielded by humans often use more powerful explosives. But is also true that the propellant in firearms is designed to deflagrate (burn very rapidly) rather then detonate, which also artificially limits its power. The reason for this is actually simple, beyond the implications as to a weapons structure, supersonic detonations are not always the most efficient way of moving a bullet. Detonations produce super-sonic shock waves (by definition) which can pass right through the bullet carrying much of the energy with it. Much like when you get knocking in a car engine, its the same principle.

It is also untrue that firearms can get much more efficient than they are currently. In the case of most hand weapons (especially rifles) the limit has already been reached. There are few ways to further increase it without compromising the weapon in some way. Increasing the barrel length beyond a certain point will only increase friction and reduce efficiency, indeed many rifles have barrels already beyond this length. Firearm chambers are already sealed nearly perfectly and any other loss of efficency (such as to drive reload) is a design choice. There is simply a limit to how much energy can be extracted from expanding propellant. 30% isn't actually bad mind you, for a heat engine (which is what a firearm essentially is) its actually pretty good.

However many of these objections simply don't apply to railguns. First and foremost railguns are not heat engines, and so their efficiency is not governed by the same laws that a firearm is. And so it can theoretically be much greater. And since a railgun does not get its power from a chemical propellant, it does not have to worry about using an energy source that is overly energy dense. If we found a matter-electricty conversion engine tomorrow, we could theoretically plug it into a railgun if we wanted. Using a nuclear device to propel a bullet would have obvious problems. Thirdly since the energy for the bullet is generated all along the 'barrel' of a railgun, there is no need to build a combustion chamber strong enough to contain the detonation/deflagration. Since railguns have no need to contain the propellant gasses, they can be built with only 'rails' instead of full fledged barrels, reducing friction losses. And so on.

It is at least true that for a given level of recoil there is a limitation to the amount of extra power a railgun can produce. However to some extent the greater efficiencies of a railgun give at least some advantage on this front as at least some of the recoil a firearm produces is wasted in accelerating propellant gasses out the front of the barrel. But there is another way to look at it. Since Railgun efficy is proportianal to the momentum of a bullet, like recoil, it is more efficent for a railgun to deliver a smaller, less massive, projectile at higher velocities (and thus KE). Firearms actually grow less efficient as bore size is decreased as there is more friction per unit of mass. Giving railguns an advantage in this area.

Lastly (and this is looking farther down the road then SR is currently at) if battery tech and railgun efficiency increases substantially beyond the limits firearms have currently hit, this will have implication on to the amount of rounds a person could carry.


Again and again, car engines are a terrible comparison for railguns. Gasoline is like 5 times as energy dense as the very best explosives. If you tried to power your car with gunpowder you mileage would be terrible. Unless someone figures out a way to power handguns with gasoline (not entirely crazy actually, check out liquid propellants for firearms), this comparison is moot.

Just some quick figures again for you:
Gasoline (no oxidiser): ~45MJ/kg @ 25% eff = ~11MJ/kg
HMX: ~7MJ/kg @ 30% eff = ~2.1MJ/kg
TNT: ~5MJ/kg @ 30% eff = ~1.5MJ/kg
Lithium Ion w/ Nanowires: ~2.5MJ/kg @ 50% eff = ~1.3MJ/kg
Zinc Air: 1.5MJ/kg @ 39% eff = ~.75MJ/kg

The gap bettwen modern and SOTA batteries and chemical explosives isn't that great. But the difference between them and gasoline is huge. Also note that my calculations for modern firearm energy are pretty generous as I used TNT, since I didn't have any energy density figures for guncotten and what not.

Recoil is based on momentum, not KE. So recoil increases linearly with velocity, not with the square of the velocity. So you can reach absurd energy levels without tearing your hand off.

Other things to consider is that no non-sealed military weapon will have a caliber of less than 3-4 milimeter due to fouling issues. If you take a 1/100th of an inch chunk of dirt and compare it to a 1.6mm bore, you'll be looking at a 10%+ blockage of the bore.
Railguns are also like bullets in that the round has to not only impact the target but it also needs the effective cross-section to create a big enough hole for enough air to get in and juice to get out to make a difference. Popping a bunch of 1.6mm holes straight through most areas of the body will just leave a bunch of self-sealing pinhole puncture wounds until sepsis kicks in a few days later.
Vehicular damage effects like spalling, friction flames and overpressure largely don't exist when you're shooting people, so you need to take this into account as well.

I'm not sure that's really true. I doubt much test has been done on the effects of 10km/sec projectiles impacting people. I suspect that at some point you will get the "prairie dog hit by varmit round" effect, where the temporary wound cavity is larger than the dimension of the target and the target essentially explodes.

There are countless ways of dealing with this if it is indeed an issue. Putting a shutter on the barrel would be one of the simplest. But I doubt dirt fouling will be a huge issue. At the energies a rail-gun (or a rifle even) dirt and other lightweight debrie is simply going crushed, flattened, and blown away. However since rail-guns don't rely upon rifling and using copper to seal the barrel, they will not have to worry about fouling effects in the rifling, which is a non-trivial concern for conventional firearms (instead they will have to worry about not ripping the rails apart at hypersonic velocities).

Spoken like someone who has never had 1.6mm holes drilled through their internal organs . I doubt the experience will be quite as pleasant as you imagine. In addition, some other nasty effects can expected to occur when the bullet velocity hits about 1.5km/s, the speed of sound in water. This is very fast for a rifle bullet (in fact I can't think of any rounds that go this fast), but might be only moderate/low for a rail-gun round. Once you crash that threshold you are going to start sending supersonic shockwaves through the human body (which is mostly water). The effects of this are unknown, we don't have a lot of experimental data for sending Mach 3+ rounds into people, but are probably not going to be very good. In addition a high enough velocity round could start to bring in compressive heating effects in the target, flashing your internal fluids into steam (probably not fun either), technicaly these will start about 1.5km/s in people, but I'm unsure when exactly they will start to be significant. In fact one of the reasons many of the effects you list above don't exist when your shooting people is because in large part the rounds you are shooting people with simply aren't going fast enough. A rail gun solves this problem.

And all this without specifically engineering a railgun round to have nasty effects, which is possible as well. You can design a railgun round to detonate, catch on fire, fragment, expand, or sprawl just as you could any other round. Depending upon the exact effect desired the engineering might be tricky, but its far from impossible.

The "varmint load" issue is caused by the temporary cavity caused by the bullet impact being larger than the critter. This will not happen when you shoot a person of normal size and weight. Temporary cavitation has also been disproved as a factor in wounding people (but this was the prevailing theory in the 1980s and led mto the swap to 9mm Para pistols in the US by many agencies) as most of the body is full of elastic tissues that simply snap back into place once the projectile has passed, it doesn't give you much in the long run.

Fletchettes (which is basically what most railgun ammo will be) were also demonstrated as being horrible manstoppers as by their use in shotgun shells against the VC in Vietnam. They popped a bunch of holes in them and you hoped that they bled out internally as they kept running or fighting until you found them later with a bunch of pinhole wounds all over the corpse. Buckshot #4 was the preferred loading as it combined (and still does so) the best mix of penetration of human targets with projectile count and good patterning. The one saving grace for fletchettes in Vietnam was beehive rounds but that was a full-on artillery/tank cannon loading and typically hit the target with 10+ projectiles in one go.

Also, 10km/sec is a very extreme example as any loading (let alone the smallish ones assumed with man-portable railgun systems) will start to melt and deform through atmospheric friction once it breaks 4.5 km/sec or so. If you don't mind your rounds flaring, turning into molten goop, and then flinging off in every way but straight toward your target then 10 km/sec is the way to go. If you want an effective manstopper with long range then you probably want a tungsten/DU fletchette with a conductive coil around it traveling at less than 4 km/sec and a heavier tail than it's nose so it tumbles in the target once it hits. Infantry weapons can stick with simple steel projectiles as they won't be shooting more than 800m or so anyway.

Good points.

The fouling issue is handled by the idea of a hypersonic projectile made from hard materials being deflected even slightly while still under acceleration in a technologically complex computerized infantry murder machine. I would hate to see the effects of a 2km/sec slight deviation in a projectile while still going through a precision accelerator, myself.

I've also smashed my hand with a hammer before. It sucked, but it wasn't lethal and I was able to work the rest of the day. An infantry weapon needs to be able to stop their target right fucking now so popping a 1.6mm hole in an internal organ sucks but if it's not immediately debilitating through adrenaline, psychological conditioning, etc. than it's a wasted shot for all intents and purposes. Yes, you could probably stop targets with skinny little projectiles in ridiculously diminutive proportions but you can get the same terminal effect from a larger projectile at lot easier from a maintenance, logistics, and manufacturing standpoint.

I would propose a dense plastic/tungsten projectile with a conductive coil around it that is heavier in the base than the tip in a caliber of about 4mm or so. It's big enough that you don't have to rely on iffy physics to work like shockwaves for terminal effect but still skinny enough for the projectile to take advantage of the high magazine capacity, aerodynamic shape, and excellent penetration of light armored vehicles. It also eases the strain on manufacturing to insane tolerances, improves reliability under battlefield conditions, and allows for the weapon to be worked on in the field rather than in a clean room.

I think one of the harder parts of a magnetic weapon would be feeding the rounds via a clip as the strong fields would effect the unloaded rounds as well as the loaded ones.

The whole 'while still under acceleration' bit is part of the reason why fouling, especially from something as flimsy as dirt, is not likely to be an issue. This means there are still forces within the gun putting energy into the projectile to keep it on the proper trajectory, and not careening around destroying the gun. And frankly the amount of resistance or latitudinal force some dirt can put on a round is trivial in comparison to the force the round is already operating under. The 'rails' are already having to hold together while a bullet is screaming down them at some insane velocity. The slight cross wise force some dirt my introduce into this equation is negligible. A speck of dirt doesn't suddenly make a rifle round start tumbling in the barrel, nor does a some dirt in a cannons barrel. The forces at play aren't any different for a small diameter railgun round either. Dirt and other non-substantial debris simply can't impact enough force to change things.


I doubt that hammer was moving at 1.5km/s or more though. At these speeds different forces are at work. In particular as I said before past 1.5km/s or so the shock-waves inside the human body are going to be super-sonic. The impact of these waves is going to be much more traumatic on the human body. I would not hazard a guess as to their ultimate effectiveness, except to say that trying to model their effects by the example of the waves slower rounds produce is bound to be incorrect. The phenomenon will be whole different and much more violent. In some sense it would essentially be as if an explosive was set off inside the human body.

Most everyone in the industry uses energy. The Handloader's Digest and Lyman Reloading Handbook both list recoil energy. Remington distributes a program called Shoot! that also quotes energy rather than momentum (http://www.remington.com/products/ammunition/ballistics/remington_shoot_ballistics_software.asp)

That's because muzzle energy varies linearly with force for equal muzzle lengths. (E=F*d) For any given weapon application (holdout, pistol, SMG, assault rifle, sniper rifle, assault cannon) you can consider muzzle length to be fixed. So energy is just as relevant in recoil discussion as momentum.

That means that you can NOT get absurd energy levels without tearing your hand off. Or more appropriately, without breaking your wrist.