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First off, let me point out that handgun enthusiasts are quite opinionated, and there are a few points of contentions on the subject. There are some debates that have gone on for decades. For instance, try asking some hunters about the theory of "hydrostatic shock" and you'll get an ear full. So if you are a handgun expert, and you read something in the following that you disagree with, please don't get excited. Just send me an email and we'll try to present your side.
If you are sure you won't hit anything but the space pirate, a standard handgun like a .45 automatic might do. One might think that the recoil would be uncontrollable in free fall, but both Dr. Schilling and Erik Max Francis are of the opinion that such recoil is vastly overrated. In a firefight, you'd be trying to keep behind some cover (or you'd be dead) so you'd be braced in some fashion. Any bracing at all would take care of the recoil. Erik (working with somebody else's figures) calculates that the recoil will spin you at the minuscule rate of a few degrees per second. (bullet momentum 4 kg m/s, fired from 40 cm from the center of the axis, the angular momentum imparted to the marksman is thus 1.6 kg m2/s. Divide that by marksman's moment of inertia, and you get an angular speed of 0.05 rad/s, or less than 3 deg/s.) If you wanted to use your handgun for propulsion, Trip the Space Parasite calculates that a .45 automatic will give 0.12 m/s of deltaV to a 50 kg person.
And if you are a space pirate captain who often has to deal with mutiny, you might want to invest in a futuristic version of a duck's foot pistol. A sidearm that fires on all four barrels over a wide angle with one pull of the trigger is a great equalizer when you are outnumbered.
James Borham has another often overlooked concern:
Speaking of bangs, one thing that virtually every sci-fi writer ignores is the fact that any boarding party is going to need hearing protection. Loud noises (like gunshots) are bad for ones hearing, and narrow metal corridors make great echo chambers, increasing the effect. A modern SWAT team uses suppressed weapons not for stealth, but to protect their own hearing. Anyone firing a weapon on-board a starship is going to have the exact same problem, only many times worse.
Propellent and Lubrication
A conventional bullet has oxidizer inside the shell, it does not require atmospheric oxygen in order to fire. However, conventional handgun lubrication oil will boil away in vacuum, leaving a gummy mess. Unless special lubrication is used, the handgun is likely to jam. This is mentioned in The Venus Belt by L. Neil Smith, and also includes a mention of the effect of a 200 degree thermal shock the weapon undergoes when moved from sunlight into shadow. Thermotolerance of all components in the gun are important, many mechanical devices really don't like the idea of going from room temp to -60°F over a short period of time. The weapon might work shortly after it was brought out of the airlock, then suddenly seize up.
Evan Dorn notes that the lubrication question is not quite as bad as I make it out to be:
While thermal expansion might indeed be a problem, lack of lubrication probably isn't on the timescales important in a gunfight. The mechanisms of basic firearms are sufficiently simple that they will generally operate just fine without any lubrication at all, or even when coated inside and out with dust, grit, or mud. Lubrication serves only to reduce wear over the long term. One of the favorite "torture test" approaches used to demonstrate the durability of a firearm, in fact, is to disassemble the gun, clean all the parts with a degreasing agent, reassemble it, and put a few dozen rounds through it. (See e.g., XD Torture Test -- scroll down to "The Chemical Degreaser Test".) A revolver, in particular, has only three or four moving parts and should operate under almost any conditions.
In other words, vacuum will do terrible things to a handgun's lubrication, but we don't need no steeenking lubrication anyway. However, there seems to be some controversy on this point, with heated debate between the pro-lubrication and con-lubrication factions.
If one is merely transporting the weapon through a vacuum environment but does not intent to actually use the weapon in vacuum, James Borham has the solution:
On the subject of protecting guns from thermal shock and drastic pressure changes, we already have some experience. When a solider executes a HALO (high altitude, low opening) parachute jump, he goes from STP to a very cold, low pressure environment and back to STP in a very short time. The solution? Stick weapons and other equipment that wouldn't take well to the hostile environment in insulated, airtight bags. The insulation ensures the weapon might get cold, but won't suffer thermal shock, and the inside of the bag says at atmospheric pressure the entire time. The same could be done with weapons in space: in vacuum you would be limited to a knife, and some kind of laser pistol or specialized slug thrower, but once you get inside the other ship, you can simply unzip the bag on your chest and pull out whatever kind of gun you like (e.g. short barreled assault rifle, semi-auto shotgun, BFG 90000, whatever).
Mike Van Pelt says that if protecting the spacecraft from clumsy shots has priority, frangible rounds may be the answer. These have been suggested for use by armed airline pilots, who also worry about the damage done by stray rounds. The Glasser Safety Slug was invented back in the 1970's, the current state of the art is the MagSafe. The good news is that they affect human targets far more effectively than spacecraft hulls. The bad news is that the penetration is reduced to a point where the space pirate's arms can offer their torso significant protection. And if the pirate is wearing body armor your handgun has become almost worthless. To make it worse, certain types of space suits are almost as good as body armor.
There is also the matter of vacuum welding and evaporative bonding and outgassing from plastics, coatings for the barrel, propellants in the bullet. C. James Huff notes that a conventional firearm will overheat far more rapidly in vacuum, making an assault rifle practically worthless. James Borham points out that in vacuum a laser weapon will overheat even more rapidly than a conventional firearm.
Other novels mention special muzzle brakes that vector the exhaust in useful directions. These novels include Eon by Greg Bear and Nightrider by David Mace. They generally try to vent in an "X" pattern centered on the tip of the barrel with the arms of the X perpendicular to the barrel. This tries to stabilize the barrel while not allowing the exhaust to obscure the sight picture.
Also note that a handgun for vacuum use will require an over-sized trigger guard to accept a space suited finger. András Bónitz mentions that many pistols today have large trigger-guards for gloved hands. However, a space suited finger is huge compared to a gloved finger.
Nightcrawler points out that revolvers might be popular in free fall, since other weapons eject their spent cartridges. Hot brass flyiing around the compartment could cause all sorts of problems. A cartridge floating inside a control panel and shorting out a critical component could ruin your entire day.
This is total space opera without a scrap of real science, but I couldn't resist.
Going up to a blank wall, he manipulated an almost invisible dial set flush with its surface, swung a heavy door aside, and lifted out the Standish - a fearsome weapon. Squat, huge, and heavy, it resembled somewhat an overgrown machine rifle but one possessing a thick, short telescope, with several opaque condensing lenses and parabolic reflectors. Laboring under the weight of the thing, he strode along corridors and clambered heavily down short stairways. Finally he came to the purifier room, and grinned savagely as he saw the greenish haze of light obscuring the door and walls - the shield was still in place; the pirate was still inside, still flooding with the terrible Vee-Two the Hyperion's primary air.
He set his peculiar weapon down, unfolded its three massive legs, crouched down behind it, and threw in a switch. Dull red beams of frightful intensity shot from the reflectors and sparks, almost of lightning proportions, leaped from the shielding screen under their impact. Roaring and snapping, the conflict went on for seconds, then, under the superior force of the Standish, the greenish radiance gave way. Behind it the metal of the door ran the gamut of color - red, yellow, blinding white - then literally exploded; molten, vaporized, burned away. Through the aperture thus made Costigan could plainly see the pirate in the space-armor of the chief engineer - an armor which was proof against rifle fire and which could reflect and neutralize for some little time even the terrific beam Costigan was employing. Nor was the pirate unarmed - a vicious flare of incandescence leaped from his Lewiston, to spend its force in spitting, crackling pyrotechnics against the ether-wall of the squat and monstrous Standish. But Costigan's infernal engine did not rely only upon vibratory destruction. At almost the first flash of the pirate's weapon the officer touched a trigger, there was a double report, ear- shattering in that narrowly confined space, and the pirate's body literally flew into mist as a half-kilogram shell tore through his armor and exploded.
The good old MBA Gyrojet pistol is worth looking at. This out of production weapon actually fired rocket bullets. It had practically no recoil, but alas, as we saw, recoil isn't a problem. The tail jets were angled to spin the rocket bullet in lieu of rifling. Problems included slow burn times (which meant if your target was too close, the bullet didn't have enough time to get up to speed) and poor accuracy.
As it turns out, the poor accuracy was due to the ammunition, not because rocket bullets are inherently inaccurate. The MBA ammo suffered from shoddy manufacturing and poor quality control.
The pistol had a mass of 0.4 kg. The pistol holds six rounds in the magazine. Each .50 caliber rocket "bullet" had a mass of 9 grams (6.65 grams of rocket + 2.5 grams of propellant). Each rocket has a low velocity at the point where it exited the muzzle, but by the time it had traveled 9 meters it had accelerated to 380 m/s.
But with some development, the weapon might be redeemed. The Deathwind project is attempting to create the next generation of gyrojet weapons. Or if you prefer the brute-force approach, the rocket bullets could be enhanced with explosive warheads or made into radar-guided or heat-seeking missiles.
Coridon Henshaw suggests special fusing for the explosive warheads, so the shaped charge will go off if they contact flesh or body armor, but not if they hit the hull. He says another possibility is a multispectral sensor and sighting laser that will disallow firing if the line of sight ends at something that is part of the spacecraft. Include a manual override in case some diabolical space pirate figures out how to make their body armor look like hull plates.
The Gyrojet did have a remarkably jam-proof design, due to the small number of moving parts. Instead of a movable firing pin struck by a hammer, there is a fixed pin at the back of the chamber. The hammer strikes the front of the rocket, forcing it back onto the fixed firing pin. The rocket shoots out the barrel, simultaneously re-cocking the hammer. The hammer is initially cocked by a lever on the side of the sidearm, in an arc-like groove above the trigger.
What caused the MBA company to go bankrupt was the fact that the military didn't want the Gyrojet, and there was no civilian market for a weapon whose ammunition costs over a dollar a shell, with no possibility of re-loading the shells.
The Gyrojet: an ancient toy or weapon, depending. It was a rocket pistol, made during the 1960s, then discontinued. This one had been stolen from someone's house and later sold to McAllister, secretly, a full twelve years ago.
A rocket pistol. How could any former Buck Rogers fan have turned down a rocket pistol?
(ed note: In the original 1928 Buck Rogers comic strip, the American freedom fighters are armed with rocket pistols, while the sinister Mongol Hordes have deadly disintegrator rays.)
Erik says another possibility would be some sort of flechette weapon. This is kind of a shot-gun that fires a swarm of darts instead of buckshot ("flechette" is French for "little arrow"). They look like nails. In the shell, a group of flechettes are held together by a plastic frame called a sabot, which falls away when the load exits the muzzle. Light flechettes are twenty to a shell, heavy are six to a shell. Like shotgun shells, they are good for causing large amounts of damage to the intruder in one's apartment, but failing to penetrate the wall so as to not annoy the neighbors. Unlike shotgun shells, they are good at penetrating body armor.
Well, the heavy ones are good at penetrating. James Borham has further details:
Light flechettes are only good against soft body armor; rifle plates will stop them cold. Additionally, light flechettes lack the stopping power of buckshot against unarmored targets.
I couldn't find any info about heavy flechette shells, but I would imagine they behave very differently from their lighter brothers. With each flechette having the mass of a 000 buckshot pellet and likely being made from very hard material (at least hardened steel, probably tungsten), these shells will exhibit rifle grade penetration against everything. On the plus side, everything includes hard body armor.
All around, a shotgun would be quite at home on a ship. Light flechette shells or light bird-shot would protect the ship from misses, while heavy flechettes or saboted slugs would provide penetration against heavy armor. Just remember your hearing protection! Shotguns can't be suppressed, and are very, very loud indoors.
SF author Michael Z. Williamson begs to differ.
Actually, the first weapon suppressors (silencers) WERE for shotguns. There's no trick to silencing them, though it's a bit bulky.
Birdshot will not reliably stop a person. It generally causes a flesh wound only. There are no projectiles that will reliably stop a person and not also punch the wall.
Glasers are still considered better than Magsafe by many people, though the fad for both seems to be fading.
Mr. Williamson cites The Box O' Truth as his source. They do test fires on a lot of weapons, for penetration and damage.
In the "visually impressive" department, we have the Whitney Wolverine. At .22 calibre it has no stopping power, but boy, does it does it look futuristic!
The legendary Gharlane of Eddore once said:
Or how about the Whitney "Wolverine," the .22 pistol from about forty years back that looked like it had come from sixty years in the future? I once helped out a friend in dire need of hand-props for a SkiFfy movie by suggesting he use some of those. Saved him a bundle.... the problem was prying them loose from the actors so we could return them to the folks we'd rented them from!
In reference to the top picture at the right he said:
Note that the picture is one of the blued/anodized models; the ones you want to use as hand-props in SkiFfy movies are the stainless-steel and passivation-anodized ones, a creamy silvery color with iridescent rainbow highlights. some production runs used a magnesium-aluminum alloy shroud which wouldn't take bluing, but anodized nicely, in some very pretty colors.
Interestingly enough, the Whitney Wolverine is now back in production from Olympic Arms.
The pistol grip of the Wolverine may look weird and futuristic, but it has an ergometric design, and is reportedly quite comfortable to hold.
Keep in mind though that when a SF movie director on a budget uses "exotic" (i.e, not commonly encountered in the United State) firearms as props instead of making them from scratch, they run the risk of the infamous "I Know That Gun" problem. This is when you get a steady stream of gun enthusiasts pointing at the movie screen while saying "I know that gun..." There is a nice list here, and another one here.
Beretta U22 Neos
Recently, the Beretta company released a target/plinking pistol with the same futuristic look as the Whitney Wolverine. Called the U22 Neos, it too would not look out of place in a spacecraft.
Zathras9 brought to my attention another visually impressive firearm: the Magnum Research Lone Eagle.
While this is a single-shot breech-loading target pistol, it chambers rifle ammunition with five times the volume of a comparable caliber pistol round, making it a heavy hitter. With only minimal alteration, the design would work as rocket-firing pistol, especially if the telescopic sight contained a dedicated ballistic computer.
One could even make a good case for keeping it a single-shot breech-loader rather than a magazine-fed design like the GyroJet: it's probably not a good idea to have multiple round of volatile ammunition contained within the weapon at all times. Better to keep the rockets that it fires in a separate container and load and fire the weapon only when necessary.
This might be even more credible it fired a wide variety of rocket types: anti-personnel, armor-piercing, biochemical, concussion, explosive, gas, incendiary, marking, netting/binding, smoke or thermonuclear. There's even a precedent of sorts in the "Caster" using in the anime/manga series Outlaw Star, although that fired magical spells rather than technological warheads.
If I were making a 80th anniversary Buck Rogers movie, this is what I'd use for the standard-issue rocket pistol.
The weapons can also have a mystique about them. Pictured is the legendary Cosmo-Dragoon from the anime of Leiji Matsumoto. His astro-automatic is a variant on this. The weapon was modeled after the Colt 1848 Dragoon Pistol. In his anime, there are only four of these weapons in existence, and they are the only weapons capable of killing a machine person. It is truly a space warrior's gun.
This was another one of those times when Bigman was glad he carried a needle- gun even in the face of Lucky's disapproval. Lucky considered it an unreliable weapon, as it was too hard to focus accurately, but Bigman would sooner doubt the fact that he was as tall as any six-footer as doubt his own skill. When Summers didn't turn at Bigman's shout, Bigman clenched his fist about the weapon (of which only half-inch of snout, narrowing to a needlepoint, showed between the second and third fingers of his right hand) and squeezed just tightly enough to activate it.
Nightcrawler has found several marvelous firearms that were perhaps ahead of their time, but never quite made it. They would be very appropriate for a classic future setting. Nightcrawler advises anyone doing research into such historical firearms to go to Maxim R. Popenker's the "Modern Firearms & Ammunition" site.
Most of these firearms feature the "bullpup" arrangement, where the magazine and the action (mechanism) are behind the handgrip and trigger, instead of in front as is conventional. This shortens the weapon's total length and improves the balance. As a drawback, most bullpups have a specific "handedness". If a left-handed shooter tries to fire a right-handed bullpup, the bullpup will insert the red-hot spent casing up their nose, grab their ear, and attempt to load it into the firing chamber. RanulfC tells me that 90% of all bullpup designs can be easily reset from one handedness to the other.
In the AUG case, pop one pin, pull the charging lever/ejection port forward, rotate, push back in and seat pin. Done.
For an in-depth look at advantages and disadvantages about the bullpup, read Anthony Williams' article.
I'm very familiar with firearms of most types, and I honestly have no idea how this thing feeds or ejects. It's possible it uses some kind of ejection tube, where the brass falls out of the front, but that's only a guess.
The Korobov TKB-022 has a vertically moving breach and it ejects out the front, above the barrel, as noted [on "Modern Firearms & Ammunition"]. The relevant text is quoted below:
"The TKB-022 assault rifle is gas-operated weapon with annular gas piston located around the barrel. To achieve minimum length, it is assembled into bull-pup configuration and uses vertically sliding bereech block (bolt), rather than traditional and most common bolt that cycles back and forth. Since the movement of the bolt (breechblock) in this design cannot be used to extract, eject and load cartridges, Korobov developed a special U-shaped rammer / extractor, that strips the frech cartridge from magazine, pushes it into the chamber, then, after the discharge, pulls the fired cartridge case back from the chamber. Upon feeding the next fresh cartridge, the fired case is pushed forward and slightly up, into the ejection chute above the barrel. Spent cases finally fell off the gun above the muzzle. Gun was capable of full- and semi-automatic fire, with combined safety / fire mode selector switch located above the trigger on the left side of the gun. The gun housing was made from reddish-brown plastic, with metall structure hidden inside."
Note the angled-forward ejection, allowing left-handed use of the rifle.
LAPA FA 03
An experimental Brazillian design from the 70s.
Was formally adopted by the British but never put into service. The idea of a service rifle equipped with an optic and utilizing folding back-up iron sights is accepted now, but it was far ahead of its time when the Enfield was designed.
High Standard HS-10
A bullpup autoloading shotgun with a built-in light. Weapon lights are common now (and likely would be in space, because it's dark on a ship if the lights go out), but this design was ahead of its time. It would have been better served with a full-length magazine tube, allowing it to hold more shells.
András Bónitz has also be doing some studying of futuristic looking weapons.
First off, THE weapon of the (near-by) future. For settings that try to be quite realistic and want to show off a powerful weapon, then I would recommend the Heckler & Koch G11. It looks futuristic, it is futuristic and... it looks cool. It's also something that would make some gun nuts like me drool.
It was a experimental weapon that showed positive results. It was part of a research project to improve firearms issued to soldiers. The weapon is special in its ammunition: namely there is no casing for it, or more accurately, the casing is flammable thus removed when the bullet is fired. Among other things, this results in a higher rate of fire and increased accuracy, all while being lighter. These are the three most looked-after properties when it comes to assault rifles for the regular soldier, thus quite reasonably the next direction to go. Plus, you don't have to worry about spent shells because there are no shells. The only thing I can't get a hold of is the ballistic properties of the ammunition.
A curious thing about the G11 (aside the advantages of its caseless ammunition) was that it was designed to fire in burst mode. Burst mode means that pulling the trigger will fire sequentially a fixed amount of bullets (here, three bullets) and actually had a higher rate of fire in burst mode than in either semi-automatic (pull trigger = 1 bullet, for those that are unfamiliar with such terms) or automatic mode (pull trigger = bullets come until the magazine is empty or the trigger is released). This helps conserve ammunition and improve accuracy due to the mechanics of recoil. Supposedly, the recoil was felt only after the bullets left the gun.
The G11's caseless ammunation was developed during the "micro-calibre craze" ,a subject beyond the scope of this document (but if you are interested, look up "Project Salvo"). Thus was why the bullets had the calibre of 4.7mm (4.7x36). Like most micro-calibres, lethality was questionable, a fact that was offset by the G11's burst mode. A single bullet may not cause enough damage to incapacitate a target, but three bullets will.
Since this may be hard to come by, here is the performance of the 4.7mm G11 bullet: it weighted 3.4 grams, had the sectional density of 0.210, had the muzzle velocity of 930 m/s with the energy of 1470 Joules and had the recoil impulse of 28. (Sectional density is the momentum of the projectile per square milimetre).
It should be noted that caseless ammunation is much more fragile than regular cased ammunation, a fact that plaqued many other attempts at caseless ammunation since. Dynamit nobel was able to create a stable-enough propellent to make the weapon battle-worthy.
One might wonder that if the weapon was so great and so interesting, why was it not adopted? The answer that it was about to be, but history interfered. The weapon was commisioned by the Bundeswehr, the armed forced of Federal Germany to replace their old G3 rifles. The G11 was extensively field-tested and was about to enter adoption when the Berlin Wall fell. Reunification drew away funds from many projects, including the re-arment of the Bundeswehr. H&K went nearly bankcrupt due to this (and was brought by Royal Ordance, Britain), thus it is understandable that it is rather unenthusiastic to try it again. However, attempts at caseless ammunation may see the light again or possibly underway already.
It might be ideal to increase the bullet's size and propellent loading if that were to happen. Something along the British EM-2's 6.5x43 or the current spec-ops special 6.8x43 Remington would be considered ideal, giving appropriate conversion to caseless ammunation.
The other end of the spectrum of using bigger bullets, is using small bullets but using them very fast. This is what resulted in the American-180.
The American 180 is very interesting because it uses a common ammunation, the 22LR, used for sport and small game hunting. The gun offsets the .22LR's lack of stopping power by simply using more of it, hence is large (starting from 165 to 270!) drum magazine. The game had the awesome firing rate of 1200 rounds per minute (compared to say, the MP5's 680 or the M16's 800), meaning that 20 bullets were fired in a single second! One .22LR may fail to incapacitate an opponent, but several will bring anyone down, even chewing trough body armour by sheer voloume. The weapon failed due to its high cost and possibly because it was unable to satisfy its niché.
I still very much like this weapon, mostly because it resembles the popular image of the "Chicago typewriter", the idea of a drumed Thompson taken out and sweeping the streets.
It appears that a company named Tactical Innovations INC has developed an "upper" for the M16 that is essentially a modern version of the American-180 and is sold online. Here is a video there that shows a man holding such a weapon one-handed, demonstrating the low recoil of the .22LR.
As for shotguns, its not just about flechettes and birdshot: there are a ton of various specialty shotgun shells, from signaling whistles propelled by the shotgun, through flares and incendiary rounds to fin-aided explosives!
Example of a possible future shotgun and fin-aided explosives Video: AA-12. World's deadliest shotgun
There are even various "crazy" rounds like the infamous incendiary Dragon's Breath, bolo (two balls connected by a piano wire, thus cutting anything in its path, obviously unpredictably), self contained TASER slugs etc.
Of course, these specialty shotgun rounds are exactly that: special rounds for a special purposes. If you want to kill something, you will obviously just use buckshot or slugs or some similar variant. My point is that a shotgun would truly be quite at home on a spaceship as it is a versatile launching platform for a variety of weapons. With a little imagination and microscopic amounts plutonium, you could make even more uses for it. For example, with using a blank shot you can MacGuyver a shotgun to shot a grappling hook for you! Granted, it would take a little bit of engineering to figure out how it would do that, but still, I would like to see a laser do that.
Thus for your typical space jockey getting from one bizarre situation to the next, it would be a handy weapon, even if more powerful and futuristic weapons are available.
In sci-fi terms, think of a shotgun as a low-tech equivalent of a phaser. It's "good for everything, great for nothing" type of weapon when it comes to roles, with one big weakness.
The main issue with shotguns, is that cannot reliably pierce (level 4) body armour in almost any (known to me anyway) loading. This is a very big limitation, because most armies nowadays have body armour. I am sure that someone, somewhere is likely to develop an armour-piercing slug, but why do that when your General Issue Assault Rifle can already penetrate most types of body armour by default? Explosive shotgun grenades may seem dandy, except that 40mm grenades can deliver far more ordinance and there is a weapon devoted to just that task.
However, for broad purposes, the shotgun is an attractive weapon. Assuming you can carry the rounds, you can hunt with it, you can blow a few things up, you can incapacitate someone with it and it can be a fearsome weapon in close- quarters. For starship crews that might not want to lug around 5 different weapons that all fit for only one role, this might be an attractive weapon, especially if they expect to do special missions.
The NEOSTEAD is a rather innovative pump-action shotgun: it has two tubes for ammo, meaning that you can put slug type X in one and switch over to slug type Y that's in the other without reloading. Can be handy if you intend to exploit the ups and downs of different rounds.
Oh, and the shotgun is bullpup, allowing a large barrel while not being very large. This makes it quite compact compared to other combat shotguns. The pump-action is rather unique so far (forward-backward rather than backward-forward), but has been described by those that fired such a weapon as faster than conventional pump-action weapons.
Plus, it looks cool and has enough polymer in it to be branded "futuristic".
As a closing note on shotguns, I accidentally stumbled upon the patent for their silencers.
On the note of bullets and shells, here is an old dream: explosive bullets!
Explosives bullets have also been mentioned in non-fiction or semi-fiction in Frederick Forsyth's "Day of the Jackal" (an assassin trying to kill the a French president and how he does it). In it, the Jackal (the assassin) and the Armourer (a black market master gunsmith) discuss their business. The Jackal not only needs a gun that kills someone, but a one-off, a gun made specifically for one job and for one set of circumstances. The Jackal needs to gun to be of certain sizes, so he can hide it in disassembled form. The Jackal has a specific container in mind that would make the gun pass without suspicion (the book is set in the 1960's, thus only manual inspection).
This greatly limits the gun's size, especially the bullet. The calibre and power of the bullet in question is just not powerful enough to assuredly kill someone with one shot and that's all the Jackal wants to do. The Armourer comes up with a suggestion of an explosive bullet that would keep the bullet's size but would cause severe internal damage.
Essentially, the Armourer takes a bullet, drills a small hole in it, pours a droplet of mercury into it and fills the lead right back up. The mercury's purpose is two-fold: first, when the bullet is fired, the mercury accelerates backwards into its cavity. When the bullet hits, the droplet is propelled forward in the bullet and tears the bullet apart, making lead spray outward, thus creating a cavity far larger than the bullet, causing massive internal damage. The book notes that these bullets are far too complex to be produced en masse unless done by a factory. That, and the fact that they are supposedly banned by the Geneva convention.
The secondary function of the mercury is to be hot mercury: poison, in case the target survives the shot (the book does not mention this).
Thomas L. Nielsen (B.Sc. / Case Officer of the Danish Defence Acquisition and Logistics Organization, Weapons Technology Branch ) disagrees with the feasibility of the mercury rounds.
All the tests I have seen of this concept show that the effect of filling a bullet nose with mercury is just not worth the bother. It is at best no more effective than a standard hollowpoint bullet, and far, far more expensive.
Back to András Bónitz:
A "weaker" version of these are hollow point rounds and soft-headed rounds. Technically, these are banned by the 1899 Hague Convention (third declaration, if Wikipedia is to be believed), which is part of the Geneva convention. About how this law is actually observed and followed, I would recommend getting a law student to find out.
Thomas Nielsen had these comments on hollow point rounds. First off, as he stated above, mercury rounds are not weaker than hollow points. Secondly, the proper term is "soft-nosed" rounds, not "soft-headed" rounds. Further:
Technically, the Hague Accord/convention only applies to declared warfare between undersigning nation states. Which means police, security forces, legally armed civilians, military forces engaged in "police actions", as well as, of course, the above-mentioned assassin, can use expanding/deforming bullets to their hearts' content. Most military forces, however, choose to follow the letter of the Hague Accord regardless of the type and scale of operation. See e.g. this document
Back to András Bónitz:
Moving on, I would like to point out the XM29 OICW.
The predominant feature of this weapon, aside trying to combine an assault rifle and grenade launcher while expecting a soldier to lug it around without a problem, is the TA/FC. TA/FC stands for " target acquisition / fire control system" which is, simply put, a miniature ballistic computer with its own sensors ("computerized sight"). What makes it more unique is the Air Burst functionality. Air Burst means that it can program a lunched grenade to explode at a specific moment (with special grenade only, of course).
A scenario: two guys are hiding next to a window in a building. You have to take them out from afar and without alerting them. You can't just use a regular grenade, as it would go trough the window and into the far end of the room (possibly trough an open door that leads into a hallway), from where the effects of the grenade are lessened and the lethality is questionable at best. There is simply no good way to kill the two guys without risking alerting them.
Enter Air Burst mode. With the aforementioned computer, you can program the grenade to explode at the very moment it goes trough the window. The two guys experience the explosion and possible fragmentation directly. This can work with trenches and the like. The XM307 also has air-burst capability, and can be converted into a machine gun with the replacement of 5 parts.
The important thing is the sight: soldiers waste allot of bullets to take down one guy, up to hundreds. Since WW1, soldiers always wanted sights to better kill their enemies from afar. Nowadays, we have laser-assisted targeting and stuff like night vision sights and infra red to help find targets. A computerized sight is likely to appear in a futuristic setting.
This makes the idea of a firing system that checks whether you are shooting a soldier or an important piece of equipment much more plausible.
UPDATE: Actually, it already appeared somewhat. FN right now is making the rather sleek FN F2000 that also has a laser rangefinder with a computerized sight, usable by both the rifle and the attachable grenade launcher. The FN F2000 is one of the first ambidextrous bullpup, as the age-old problem of ejecting spent cases is solved by using an ejection tube.
Also, here is something interesting: Have you ever heard the idea of mounting a camera on your gun and aiming trough that? Well, SERO supposedly actually done that with the EOP system. (ed note: something like this has been suggested for hypothetical laser weapons.)
The EOP system was developted to deal with the prime problem of recoil. The .50 BMG or the similar 12.7mm M30 (Soviet equivalent of the latter) has enormous recoil, high enough that the user cannot fire from his shoulder. The only way to use it is by bracing it on a surface, like a ground or wall and that cannot be done if the squad is attacked suddenly.
The EOP (I wouldn't be surprised if other companies developed similiar optics) helps here: it allows the shooter to fire from the hip and thus respond quickly to any treat. It also allows the shooter to fire the rifle from behind cover without exposing himself.
The future of optics is here as well, not using glass optics but what is essentially a video camera with strong zoom capacity and possibly sensitivity within the IR ranges for night-time applications. The cost, reliability and battery power is what prevents this from entering regular service, but the future may bring different tidings.
Infantry Gattling Guns
Oh, yes. One more thing: please make a footnote or something about infantry-portable gattling guns. They do not make sense on many, many levels, most importantly, there are already machine guns that have overwhelming firepower. There is simply no need for such a weapon.
Special Purpose Individual Weapon
The US Army experimented with light-weight, high velocity projectiles in the 1960s. The big downside to such projectiles is poor penetration. Lacking momentum, featherweight flechettes are easily deflected when fired through intermediate barriers (walls, trees, etc.).
Nuwan Weerahandi mentioned the XM8 rifle, a modular rifle system under development by the US Army. One of the XM8's unique features was its modularity. This modularity allowed for quick repairs, barrel length changes, and even caliber changes in the field. But for our purposes, it is admirably futuristic looking.
Beretta Cx4 Storm
I'm sure there are many other sci-fi looking weapons out there, but I thought I'd call your attention to a few in particular. The Beretta CX4 storm carbine, since I own one in .45 caliber. It certainly is a very futuristic looking weapon. Add a few accesories, like a tactical light & a scope and you have a future SWAT weapon. The ejection port & the cocking handle can both be swapped side to side.
A few weapons that would look right at home on the set of Bladerunner is the Kel Tec SU 16 C. Or the Kel Tec 16 D.
These are a few weird rifles I personally have stumbled over.
Pistol to Carbine
The Neos has an optional kit that will convert the pistol into a carbine. People who grew up in the 1960's will quickly spot the similarity to the U.N.C.L.E. Special carbine, arguably the most famous of all TV show weapons. And though it was never shown in an episode, the carbines used in the cartoon Johnny Quest can telescope down into a pistol.