An excerpt from War Among the Stars: Firearms and Ordinance of the Space Forces.
Small Arms Development Through the 22nd Century
Handcannons first appeared on the battlefield in the Yuan dynasty of the late 13th Century. This technology rapidly spread to Europe where early artillery pieces such bombards were being used during the Late Medieval Period. The Ottoman Empire was the first military to field small arms in any quantity, arming Janissaries with matchlocks in the mid 15th Century. During this era, Europe, the matchlock or Arquebus, was still used only by specialized troops, with many soldiers still being armed with pikes and other classically Medieval weapons.
It was not until the development of the Flintlock in the mid 17th Century were firearms reliable enough to be the primary issued weapons of large armies. However, it was more than just the development of the flintlock that made arming troops with firearms possible, but improvements in metallurgy, machining, metrology, chemistry, and the infrastructure of mass manufacture that contributed militaries being able to issue a standard firearm to troops.
Over the next few hundred years, every major change in the standard-issue military rifle to the armies of the great world powers was associated with major changes in firearms technology and associated manufacturing technologies.
The move from the flintlock musket to the muzzle loading rifle or rifled musket came with the improvement in the fire control mechanism from flintlock to percussion cap, and the bullet from the round ball to the conical bullet or Minie ball. From this point, significant design changes occurred quickly. The introduction of the self-contained cartridge led to the repeating rifle. The introduction of smokeless powder and the pointed or spitzer bullet, the development of chromium-molybdenum steel alloys, heat treating, and machining let to the creation of the great firearms of the 20th Century that caused so many casualties in two world wars and countless regional conflicts around the globe.
However, by the early 21st Century, firearms technology had stalled, showing only minor incremental improvements over firearms developed shortly after World War Two in the mid 20th Century. The use of aluminum and polymer shed weight, but the firearms and ammunition were fundamentally unchanged in functionality for two generations. A solider deployed to Afganistan or Syria was carrying the same model rifle as his father in Iraq and Kuwait and his grandfather in Vietnam.
Several different avenues of small arms improvements were tried in the early 21st Century, most never being adopted by any military in large numbers due to several adverse factors.
It would take major changes in technology to improve the standard-issue military small arm to adequately equip the late 21st and early 22nd Century soldiers engaged in deep space conflicts.
One technology tried and abandoned was caseless ammunition. First tested in the 1990’s the technical limitations of making a propellent that would produce reliable ignition that was simultaneously durable enough to contain the bullet and primer as well be resistant to the elements proved far too great. The properties of the binder countered the properties of the propellant. A durable binder that allowed caseless ammunition to withstand rough handling and exposure to adverse conditions inhibited the reliable complete combustion of the propellant.
The supposed benefits that caseless ammunition had in the functionality of firearm – the lack of an extraction cycle in the weapon – did not make up for the problems of chambering easily damaged caseless rounds.
The introduction of hybrid polymer cased ammunition ultimately ended the development of caseless ammunition, having the durability of traditional metal cased ammo but at significant cost and weight reductions.
Another failed technology in general-issue small arms was electronically fired ammunition. Though useful in automatic cannons in large powered vehicles or aircraft, requiring the solider to carry both ammunition and a power cell for the fire control mechanism proved to be unnecessarily complicated for any minor increase in performance, except in very limited circumstances such as precision rifles used by highly trained designated marksmen.
The greatest change in small arms technology in the mid 20th Century was the development of chemically initiated decomposing propellants. Smokeless propellants remained inherently unchanged from the creation of Poudre B and Cordite in the 1880s, based on mixtures of nitrocellulose and nitroglycerine.
The energy density of these propellants was limited and attempts at increasing the performance of the propellant increased the brisance risking damage to the firearm.
Chemically initiated decomposing propellants, commonly known as gun gel or wet propellant, were developed from satellite and rocket thruster technology, these propellents did not burn. The propellant contained a meta-stable fuel of very high energy density and a non-metallic catalyst in gel form. The firing pin would strike a pyrotechnic primer that forcefully ejected an initiator chemical into the gel causing the immediate decomposition of the fuel. These gels were able to create substantially higher bullet velocities while totally eliminating solid (carbon) fouling.
These propellents drove rapid improvements in the development of both bullets and firearms.
The performance of the propellants exceeded the capabilities of traditional copper jacketed-lead core bullets that were introduced along with smokeless propellants at the end of the 19th Century. In addition, advancements in body armor sounded the death knell for the jacketed bullet.
Transition metal/metalloid-ceramic composites, second-generation MAX phase cermets, proved to be key in improving terminal ballistics against troop armor. Bullets were engineered to have favorable sheer properties, allowing the bullets to be self-sharpening on impact with hard targets but hydrodynamically unstable in compliant media. These bullets were capable of penetrating the most advanced wearable composite armors but would yaw rapidly causing severe soft tissue damage. Cermet bullets were also able to withstand the extreme forces generated by gun gel propellants.
The machine gun would not have been possible in the 20th Century without the development of chromium-molybdenum steel alloys. Chromium and molybdenum allow the steel to retain strength and toughness at higher temperatures. Without this metallurgical advancement, any sustained rate of above that of a manually operated firearm would cause the barrel of the weapon to overheat and rupture.
Much like the propellents, current generation firearms borrow heavily from the materials and manufacturing techniques used in the production of spacecraft and rocket systems. The development of chemically initiated decomposing propellants and MAX phase cermet bullets required the creation of new barrel and bolt materials to bring this technology to fruition. Chromium lined carbon steel alloy barrels were replaced with refractory lined composite barrels. The refractory lining had existed as far back as the 20th century but was limited largely due to the extreme cost and difficulty in machining the material. The high concentration of refractory materials present in M-type asteroids has made these materials more common with the increase in asteroid mining, and additive manufacturing techniques had simplified the process of producing firearm components from them.
In the latter part of the 21st century, two competing technologies sought to unseat the firearm as the primary small arm of military forces. The electromagnetic projector, commonly known as the railgun, and directed energy weapons, such as lasers. Despite significant expenditures in financial investment and research time, no practical technology has yet been developed that can chemical propellant powered ammunition in firearms.
The railgun, and to a significantly lesser degree, direct energy weapons did find common adoption as offensive and defensive weapons aboard larger spacecraft and ground combat vehicles in the arsenals of the major Sol system armies and navies (the subject of a different chapter of this book), these technologies did not readily scale down to man-portable size.
The power consumption to performance of these weapons was the primary limitation. Aboard a vehicle, an electromagnetic gun is powered by the vehicle’s nuclear powerplant. The size and weight of a vehicle helped mitigate the recoil effect of the relativistic velocity of an electromagnetically launched projectile. The velocity of a projectile from a shoulder-fired electromagnetic weapon must be limited so the recoil does injure the shooter to such a point that the bullet velocity is well within the range capable of being produced by a chemical propellant, roughly 1,000 to 2,000 meters per second, giving the electromagnetic weapon no significant advantage. Moreover, a significant amount of shielding was necessary to mask the electromagnetic field of a charged weapon to prevent the weapon from giving away a soldier’s position or interfering with other electronic devices.
Direct energy weapons proved to be even less useful as small arms. Generation of ultra-short wavelength lasers in the X-ray or Gamma-ray spectrum, which produce the most aggressive ablation of solid targets, requires the use of a femto-pulsed free-electron laser and undulator several meters long. This limited handheld laser system to being solid-state or chemical lasers producing energy in the visible, near-infrared, or infrared spectrum. While such lasers can produce intense burns, such weapons do not produce the same soft tissue trauma as kinetic energy projectiles except at very high intensities, outside the capability of handheld devices to generate.
Solid materials are generally very poor absorbers of photon energy. Most of the energy of a laser at or near the visible wavelengths of light is scattered or reflected. Thin-film thermal barrier coatings and reflectors commonly used in solar reflectors and heat shielding on spacecraft efficiently mitigate the majority of the energy of the laser, making these weapons easy to defend against.
The laser small arm ultimately proved to be more dangerous to the user than the target. A laser of significant intensity fired in an atmosphere produces a substantial amount of scattered laser energy. Without proper eye protection, the shooter was more likely to damage their own vision than harm the enemy, especially at longer ranges.
Technology has advanced considerably in the last few hundred years, but the human body has not. The damage caused by being hit by a high-velocity projectile has proven over and over again to be extremely lethal. Given the constraints of weight, recoil, and even the range that soldiers are willing to engage the enemy at with direct fire weapons, small caliber firearms using chemical propellent ammunition still provides the optimal balance of weapon system simplicity, man-portability, and lethality for the individual soldier.
In the future, newer technology may effectively supplant the firearm, but after nearly 700 years, it seems that the gun is here to stay.
I had to take a break from the news and decided to write some more sci-fi.
I was inspired in part by a comment left in my last sci-fi post which turned me on to Larry Correia’s Best of MHN. One of his posts is ASK CORREIA 3: SCI-FI WEAPONS.
I found it fascinating and wanted to address some of the points he made.
He is a published, professional sci-fi writer. I’m not trying to amateur-splain on his turf.
However, when it comes to firearms technology, let us say that I have a tiny bit of authority from which to speak. I won’t tell you who I worked for (I won’t confirm it either so please don’t ask in the comments if you have figure it out) but I will say when it comes to military small arms and ammunition, I’ve more than seen how the sausage gets made. I’ve helped make it and even part part of creating new recipes for it.
Everything that I’ve said is grounded heavily in science and engineering that I’ve done.
Decomposing propellants are used in rocket thrusters.
I actually worked on a project for a high velocity CIWS that used the 30mm GAU-8 round necked down to 20mm, and we lined the barrels with tungsten to get them to handle a DU bullet moving at 5,000 fps. DU is where the idea of a self sharpening round comes from, and we know how to grow materials in specific crystal orientations for semi conductor production. If you can grow a bullet in a specific crystal orientation, you can engineer the ultimate self sharpening round.
Pretty much I merged the latest in aerospace and hypersonic missile tech with small arms.
I was also inspired by one of my favorite book series the Terran Trade Authority handbooks by Stewart Cowley.
I hope you enjoy it.
Nice little read. Two typos is not bag in a story that long.
I look forward to reading more of your work.
The part about the liquid propellant is pretty cool. Years back I had an idea for ttRPG setting that was sort of an alternate history/ near future setting where firearms used liquid propellant cartridges. Cool to know people with bigger brains than me came up with the same idea.
You could always tell when they were testing liquid propellant because the building (BIG Brick building) rattled differently when the gun went “boom.”
It was a fun to go to range day. The closest target was 1000m. And to watch the M1A1 drive down the track at 45mph and put two rounds into a square yard of target at 2km was damn impressive.
(Of course it was fun to watch visitors jump the first time there was a test firing. Most people have never heard an artillery piece go off. Even if it is a half mile away. Sorry for mixing units of measure.)
Nice.
I’ve always enjoyed when L. Neil Smith brings gun technology into his SF stories, because he too knows what he’s talking about.
One technology he describes that needs some discoveries that haven’t been made is handguns using electrically propelled projectiles. The power source is the issue there.
Neil has a couple of gun designs he spells out *almost* enough to let you build one. I haven’t quite figured out the Ngu Departure yet, but I do have a sketch for the action for a Herron Staggercyl. Maybe one of these days… (BTW, those can be found in his novels “Pallas” and “Ceres” respectively.)
If you haven’t been there yet, the Atomic Rockets page is a pretty cool SF resource (lavishly illustrated with old SF art and excerpts from relevant stories).
http://www.projectrho.com/public_html/rocket/sidearmintro.php
Be careful, it’s a bigger timesink than TV Tropes!
I enjoyed the read. As a retired engineer and SF fan, I appreciate the application of real world physics and chemistry. While I can suspend disbelief for the sake of a good story, when DOD or Company propaganda starts talking about this or that wizbang weapons system, especially directed energy weapons, my gut reaction is BS, you’d need to figure out how to bring the engine room of a “Nimitz” class carrier along to power that.
I did research in laser cutting, welding, and forming. It struck me just how little laser energy was absorbed as heat and how much was reflected.
I don’t see laser weapons being useful until they get into the x-ray range. Just too much energy loss. Add in atmospheric scattering and laser weapons are useless. Hence hypersonic interceptor missiles.
Lasers are interesting.
At sufficiently high transverse power densities, laser beams with wavelengths in the near-IR to visual can – to an extent – self focus in an atmosphere. (Other bad things happen, though, as J.Kb noted.)
In a vacuum they will just diffract. So unless you have a primary mirror or lens diameter somewhere between “absurd” and “ludicrous”, they’ll be pretty useless as weapons beyond a few tens of km as well. (Phased array approaches are possible but.)
Sorry for the grain of salt, and also I’m not trying to be snarky, or even pedantic…
…but, all too often I see “ordinance” when the correct word is “ordnance.”
Just sayin…
Nicely done. Larry C. would definitely be proud. Everything you wrote made a lot of sense, and is based on the rules of the world you are working in. One of the things that ruins a good story for me is when the writer puts “magic” into it without any explanation of how it works, or how it exists. If you were to write a story with some kind of armed conflict, I would certainly understand why there is a 1911 involved.
That’s sort of interesting. “When a write puts magic into it and without an explanation of how it works…”
When Star Trek first came out and became a popular show, one of the tropes it broke was that of explaining what they were doing.
If I pick up a 1911, I don’t explain how pulling the trigger causes a lever to move which moves off the sear which causes the hammer to drop, which hits the firing pin which crushes a primer which….
I pick it up and pull the trigger. When we see Kirk use a “phaser” he picks it up, pushes the button and it goes “buzzz” and the target goes away.
There is a delicate line in writing science fiction about explaining to much and not explaining enough. So you find things like the grizzled old Sargent explaining to a new recruit how to do something. Or the Cap Trooper explaining how a powered armor works because he’s writing to his civilian dad.
I think a better way of saying it, is I don’t like it when the only way that thing could work is “magic”. If you are going to use “magic” in science fiction, throw me a bone as some sort of explainer.
Orson Scott Card talks about the difference between fantasy and science fiction. For him, it has nothing to do with “magic” verse technology, it was “Is the cover art trees or rivets. If it’s trees then it is fantasy, if it is rivets then it is science-fiction”
“There is a delicate line in writing science fiction about explaining to much and not explaining enough.”
Agree totally. And, you are correct, no one needs an explanation of how a firearm operates, but they do need an explanation of why it is there. That contributes to the story, not detracts. The Star Trek phasers were not provided with detailed explanations of how they worked, but they were appropriate for the world they were introduced in. Some kind of phased energy weapon makes sense on a spacecraft, whereas a projectile weapon would not. It fits into the rules of the universe where the story happens.
On the other hand, when a weapon or technology that is out of place for the rules of the universe, that seriously ruins the story. Larry Corriea does a much better job of providing examples than I can.
Nice. Very nice. And I definitely agree re laser comments.
Couple of side comments…
One, I can highly recommend “Ignition!” by John Clark. A little dated, but a fun read on liquid propellant research. (And confirms that my choice to not become a chemist, was a good one!)
Re energy sources and energy density, part of the problem is storage density as pkonig points out, but a bigger one (imo) is release rate.
Consider that a standard 5.56x45mm XM193 round has a muzzle energy of 1.75 kJ and is moving at around 1000 m/sec. (Wikipedia.) A single NiMH rechargeable AA battery can store around 9 kJ (https://www.allaboutbatteries.com/energy-tables.html), or the equivalent energy of ~ 5 XM193 projectiles’ muzzle energy. (Granted each round of XM193 actually stores more energy than goes into the projectile’s kinetic energy – hot gas, for instance – nor is all that energy in the AA usable.)
The problem for the battery is, that energy has to be delivered in around 0.8 milliseconds. That’s not a battery, that’s a capacitor … which has pathetic energy storage density compared to either.
Funny enough, a problem with most lasers is actually waste heat removal from the lasing medium. At weapon-useful level powers, the lasing medium stands a good choice to destroy itself. Thus the continual suggestions for chemical and free-electron lasers. But anyway…
Yes, it’s both energy density and power density (i.e., energy delivery rate). You can use a capacitor charged from a battery to get a bunch of both, that’s how strobes work.
Still, though, the best electrical energy storage systems are several orders of magnitude worse than good chemical energy storage, that’s why electric cars are so expensive. Other energy storage, like the pneumatic systems that have been postulated by some people with no understanding of physics, are quite a lot worse.
Indeed. Check out how many MJs a gallon of gasoline stores, for instance…
Re capacitors, yes, but. Again, the question is how big is the capacitor. A LARGE supercapacitor (about the size of a 1-L bottle, last I checked) could in principle store the energy equivalent of a .22LR round, and the voltage and discharge rate are about right for a very small railgun. I’ve been on-and-off toying with the idea of making one for the heck of it.
Having had the opportunity to watch the discharge of a 1 farad capacitor multiple times, it is dang impressive. The capacitor filled a small truck. It was used to energize a 500 meter linear antenna array.
It put enough energy in to the environment that at 100m distance it would cause 6 to 12 mm sparks to happen between.
I’ve even seen it fuse an 110V AC power switch from OFF to on.
But nobody is walking around with a capacitor that large. And it takes a fair bit of time to charge such a capacitor.
RE “Ignition:” Early in my career, I had the opportunity to sit in on “bull” sessions with guys that worked in various aspects of rocketry testing in the fifties and sixties. To say they had “interesting stories” was an understatement. Note to young engineers and techs, pay attention when your elders are telling stories (or swapping lies) in an informal setting, you’ll be amused, and may even learn something about what not to do.
A wonderful source of such “interesting stories” is the blog “Things I won’t work with” by Derek Lowe. https://blogs.sciencemag.org/pipeline/archives/category/things-i-wont-work-with
Chlorine trifluoride is one of the more benign substances he talks about.
FOOF!
I’ve have brief experience with interhalogens. Yes, there is a condition in which glass will burn like wood and produce silicon fluoride ash. It’s mind bending to watch.
Some more:
Yes, “Ignition!” is wonderful. I particularly enjoyed the chapter about the work done with chlorine trifluoride. Yes, that exists. It’s even stable, after a fashion. But it will set concrete on fire, among other fun properties.
On SF and magic: stories about magic are fine, but good SF is not about magic. Sometimes it extrapolates human society without assuming unexpected technology. Often it does assume currently unknown technology, even generally believed to be impossible technology (like faster than light travel). The key thing of such SF done well is that the writer has a mental model of what this technology is and how it works, and its limitations. Change assumptions and you get a different story. For example, you might have FTL travel, but if a supernova goes off less than a few hundred light years away, that mode of travel stops working for a couple of centuries. That will give you the foundation for a couple of novels — by Rolf Nelson, in fact. Pick a different set of assumptions and you might get Ringworld. Yet another different set, you get Footfall. Or Lucifer’s Hammer. For each of these, you can easily state the physics assumptions, and see that they are consistently and logically applied.
This is one reason I’ve become rather fond of Alastair Reynolds’s work, especially the Revelation Space stores, but also “House of Suns.”