Firearm

Some Tanegashima matchlocks

About twelve hundred years ago in China, some people figured out that certain chemicals mixed together (such as potassium nitrate, carbon, and sulphur) exploded when brought to spark, which became known as "black powder." After some experimentation, they discovered that a tube sealed off at one end could be used to focus said explosion to propel an object at high speeds. After a few centuries of refinement, they managed to take that mechanical principle and apply it as a weapon of warfare which changed the game: the arquebus. Comparatively cheap, easy to make, easy to learn to use, and capable of penetrating all but the heaviest armor, this marked a transition away from close quarters to ranged warfare.

In modern times, firearms are the staple weapons of any nation. Speculative fiction showcases weapons that doesn't even fire solid projectiles, like lasers.

From an engineering standpoint, firearms had a big difference from previous weapons in that they don't require the user's muscle power to work. Swords, maces, and axes are swung, spears are thrust, and bowstrings need to be drawn. Even a crossbow works by storing muscle power in the bow's tension until it's released. The energy required to accelerate a firearm's projectile comes from explosive propellants; all the user needs to do is to hold the weapon, aim and set off said explosive charge. The significance of this is illustrated in the American Proverb "God made man, Sam Colt (the inventor of the first practical revolver) made them equal": that having a reliable repeating gun means that your simple brute physical strength does not mean as much in a fight as it would in a bare knuckle brawl or a swordfight (either defensively or offensively).

The firearm's bigger bro is the Cannon and its cousin is the Rocket.

A Brief History of Firearms

The Firelance, the Chinese invention that started this all

1000s to 1200s: The Chinese realize they can make barbarians shit their pants by shooting hollowed arrows packed with powder and bamboo tubes filled with powder and pebbles at them. Bamboo gradually gives way to cast iron and bronze.

1300s: Various gunpowder weapons begin to proliferate westward along the Silk Road, aided by the Mongols. Crude versions of hand cannons, grenades, rockets, and flamethrowers all see use. Despite considerable psychological effect and good armor penetration, most of these weapons are only marginally more likely to kill the target than the user and had a range of only twenty or so meters. As such, their use is not widespread. For the most part, these weapons were used by skirmishers. The fact that they were mostly used by low class soldiers meant that the smiths making them were generally not the most skilled artisans which did little to improve quality even given the limitations of the day. Even so, the designs and methods of manufacture were gradually refined and improved by various early gunsmiths through trial and error.

1400s: Hand cannons see continued and expanded use. Bit by bit from the crude handgonnes of previous centuries, the first "true" firearms evolve with the gradual development of the matchlock, taking on the basic shape of lock, stock, trigger, and barrel (which is where we get the saying from). By clamping a lighted wick into a flashpan via a trigger, the shooter is able to aim and fire at the same time, making him markedly less likely to blow his own jimmies off. Despite advances, the matchlock was unwieldy, unreliable, and generally inferior to a good bowman. The issue of course is that only England (in Europe) HAD good bowmen; bowmen were the scum of the army everywhere else. This didn't stop some inventive commanders from seeing their potential, particularly with poorly trained conscript soldiers. Some forces made a go of it by carrying two or three guns at a time and just throwing the spent ones away like a really shitty Matrix movie. Note: while we use a "weeaboo" hyperlink up there, it's worth remembering that troops like cuirassiers and even pirates did the same thing, they just did not exist by the 1400's, having more then one gun was the only way to have any real rate of fire before breechloaders existed.

1500s: Guns continue to evolve with the invention of spring-loaded firing mechanisms. The wheel-lock spins a steel plate against sulfide rocks to produce sparks (think cigarette lighters), which ignites powder a flash pan. This was revolutionary, allowing soldiers to prime their weapon in a matter of seconds instead of fucking around with a lit wick, and allowed calvary to use guns for the first time while on horseback, giving rise to the cuirassiers. It also means that for the first time, guns weren't completely fucked in the rain, just mostly fucked. They also cost a lot to make and were still not completely reliable, so most people stuck with matchlocks. Powder formulas had improved considerably, including the development of the more powerful, stable, and moisture-resistant corned powder made by wetting raw gunpowder, forming it into cakes, crushing them, and sieving them for size. Japan was particularly notable in the history of firearms for their heavy transition from blades to guns after discovering the novelty of matchlock guns, more so that any country during that time. In fact, by the end of the 1500s, they had more trained arquebusiers in their armies and produced more matchlocks than any other country to date during that period.

The flintlock mechanism. Now you did not need to light some string and put it into a serpentine before firing

1600s The wheellock is refined into the simpler and more reliable flintlock, though it would take some time to supersede the matchlock. Muzzle loading is simplified with the creation of paper cartridges, essentially the pre-measured cake mix of murder. Some German dudes came up with the idea of cutting spirals into the barrel, which they called "rifling," to spin-stabilize the bullet so that they wouldn't have to walk up right next to their targets to hit them, but this required a barrel tighter than a nun's cunt, a hammer to ram the ball in, and grooved bullets made for the gun so it could fit the rifling of the gun like the cap to a soda bottle. To put all that into perspective: well-trained musketeers could fire three to four shots a minute, while a rifleman could only manage one shot every minute.

1700s: The French invent the bayonet, allowing their troops to be choppy while they were shooty. This is the point where gun infantry tactics become the dominant (though still not only) form of fighting when guns go from one a few common infantry weapons to the primary weapon used by most infantry. Formations of musketeers go from big square blocks to lines two or three ranks thick to put enough bullets in the enemy's ranks as quickly as possible.

The mechanism of a French Chassepot, an early bolt action rifle, as well as its paper cartridge

1800s: Pretty much everything that makes up a modern firearm is invented here. Some fool came up with an explosive that would go off if you slam a hammer into it, which led to the first explosive primers. This basically involves putting explosives in ur explosives to explode your explosives. Cartridges that contain a primer, propellant, and slug, similar to modern-day bullets, are developed. By this time, wars were largely fought using firearms rather than melee weapons, though also by this time firearms were also melee weapons. in the early 1800s the bayonet charge was still an both accepted and useful tactic.

By the late 1800 inventors had finally gotten the technology to contain the force of the gunpowder explosion with a tight seal and do so cheaply. Experiments that had been done earlier like the Puckle gun (1718), Ferguson rifle (1776), and even the bizarre 1780 Girandoni Air Rifle, which was an air gun with a 20 round magazine, all failed to create breech loading rifles cheaply. See, despite that it was well known that that slotting in bullets from the rear and using a mechanism to load it into the chamber is much simpler than spending about half a minute to ram it down a long barrel, the technology was just not there as without cheap steel (cheap is important for hand guns you are going to mass-produce), getting iron to contain the explosion without deforming and leaking gas, thus weakening the shot, was a nightmare. The Industrial Revolution, among other things, gave birth to the concept of "breach-loading" and later "magazines" and simpler mechanized feeding systems like tubes, slides, cylinders, and bolt-actions. The likes of pump-action shotguns, bolt-action rifles, and lever-action rifles, and revolver and semi-automatic pistols, are developed and/or developed upon, giving a glimpse on how weapons in the future would function. Near the end of the decade, some French guys worked out that they could both improve firepower and keep their guns considerably cleaner by replacing black powder with nitrocellulose, the first of many "smokeless powders."

Just as important as the new designs that came about during this period were the new methods of production. People like Eli Whitney worked out devices such as milling machines, which allowed for the quick production of finely tuned parts which were so close in size that you could take one bit off one gun, stick it on another from the same line, and it would work just as fine. Breech loading and repeating firearms had existed for centuries beforehand, but were not cost effective to mass produce until the Industrial Revolution.

A British Lee-Enfield Bolt Action Repeating rifle

This is also the time where the first "automatic" guns are being invented and put into production. The word "automatic" is in quotes because these early machine guns were not self-reciprocating; they did not load and fire themselves and were instead manually powered. The most famous (and successful) of these weapons is the Gatling gun, which saw limited action in the American Civil War, but became much more widely used the world over in subsequent wars. But while it was the most famous, the Gatling was not the only manual machine gun developed; dozens of different types were produced during the US Civil War alone on both sides, but because these guns tended to be mounted on cannon carriages, they were treated like cannons, not the close support weapon machines guns are, so it took some time for them to hit their stride.

1900-early 1930s: The heyday of guns because of the advent of WW1. The idea of bolt-action rifles are popularized, along with semi-automatic and fully-automatic weapons. Bolt-action rifles meant that riflemen no longer had to be confined to shooting one round at a time before needing to reload as they could now load individual clips that contained 5-10 rounds a piece. Machine guns are now becoming more and more popular in the battlefields, drastically changing the way infantry would maneuver the battlefield as a single MG emplacement can effectively cripple platoons with the right positioning. Submachine guns, the first automatic infantry weapon, are developed by the German Empire and issued to their stormtroopers, giving the rest of the world an idea of the wonders of a lightweight fully-automatic weapon that could easily be used by infantrymen, which was previously restricted to crew-served heavy machine guns.

On the subject of the machine guns, if there was ever a weapon that represented this part of history it would be the heavy machine gun. to go back to an early quote "God made man, Sam Colt made them equal and John Browning (designer of a large number of machine guns including the m2 .50 cal or 12.7mm) made them civilized. We talked about the hand powered machine guns above, and while good when used correctly, these weapons have their issues. In order to use most of them, you had to be standing up to turn the crank and sustained fire was tiring, but the hand cranked guns had one major advantage: the most successful of the hand-cranked guns, like the Gatling or Gardner, had multiple barrels meaning you can fire them with little or no need to stop to let the barrels cool down. At the dawn of the 20th century, this is what the early machine guns had to be compared to when European generals went window shopping. The solution was water-cooling, which allowed machine guns to fire for countless hours with little or no failures, but at the cost of weight rendering them truly static, though highly effective, weapons. If you could point to two developments that caused the First World War's trench warfare, you can point to water-cooled machine guns and barbed wire.

late 1930s-1940s: At the start of World War II, all of the powers involved, France, England, Germany, and Russia, were armed with bolt action weapons. Over the course of the war, automatic and semi-automatic rifles started to become more common; however, only the Americans completely phased out bolt-action rifles for standard infantry by the time of the war. Submachine guns are now becoming more popular with various armies around the world, making it the staple lightweight automatic weapon for infantry troops, totally redefining urban combat due to the weapon's great effectiveness in close combat. Nazi Germany invents the Sturmgewehr 44, the first widely produced assault rifle (the Fedorov Avtomat was the first to be put into service, introduced in 1915, but production was limited due to costs). This weapon would later become the template for modern assault rifles used by the world over.

A QBZ-95 Assault Rifle, the current service rifle of the People's Republic of China, note bullpup configuration (the magazine feeds behind the trigger), thus saving space

1950s-1990s: After World War II, the US Army performed a study and determined that it took 20,000 bullets to confirm one enemy casualty; most of those rounds would miss or be spent suppressing an enemy. With numbers like that, people now realized the power of a fully-automatic rifle since they allow you to fire more and more rounds and increase your chance of hitting as compared to a bolt action rifle. As such, assault rifles become more and more common with armed forces of the world and are extensively developed upon, largely, if not completely, phasing out the old bolt-action and semi-automatic rifles used back in WW2. Iconic assault rifles such as the AK-47, M14, and M16A1 are created and show the world the power of an automatic rifle through the the numerous wars going on during the 1960s-70s, such as the Communist wars in Korea and Vietnam, along with the Soviet occupation of Afghanistan, to name a few.

2000s: With the invention of more advanced materials such as plastics and carbon fiber, along with numerous technological advancements of the modern world, firearms become more deadly than they were ever before. Fine-tuning how every aspect of how a firearm would work has allowed numerous countries to develop better and efficient ways on how to kill on a scale unseen since the Europeans developed the musket.

2010s: Development of more robust weapons (such as the POF P416 and HK 416), modularity (FB MSBS, similar to the ACR with the variantion count of a Lasgun), practical telescopic and caseless ammo (LSAT project), and ship cannon sized railguns (The Naval Research Laboratory currently working with a practical version (i.e. can reload at the same rates as an Abrams 120mm loader). Apparently, it can fires rounds with 32 megajoules of energy, or 23,601,988 foot-pounds.) So apparently even in 2017, we outpace the Imperium in development. Makes you wonder what the Dark Age of Technology holds. Also cheap rifle parts and market (at least for Americans). No seriously, you can get a basic AR for $500 or even just make it yourself. New designer rounds to outpace rounds such as the 5.56 and .308 in performance are also coming out, such 6.5 Grendel, 6.5 MPC, .224 Valkyrie, .300 Winchester Magnum, and so on.

Many countries around the world are now looking for new ways to either improve or adapt combustion-based firearms as a whole, and are looking for ways to make what were once sci-fi-only ammo and weaponry, such as laser, plasma, direct energy overall (involving the last two), gauss ,telescopic/caseless ammo, and more, a reality. While met with some degree of success, nobody (pardoning America, 'cause you gotta do something with that large budget) has found a way yet for these weapons to be man-portable (or cost-effective in the case of telescopic and caseless ammo) that a single soldier could carry these into combat or be affordable/reliable to an extent that it would be more feasible to make these instead of the traditional ballistic weaponry. There is also the problem that if you get a hard projectile (think tungsten and steel) going fast enough, it will just over-penetrate and go through a target, doing little actual damage as compared to our modern bullets that hit, create a temporary cavity the size of a dinner plate, then tumble going through the target sideways. Rounds that fragment and inbuilt post-penetration destabilization fix this, however there is little reason to use some fancy dandy half million dollar gun and ammo when a good ol' service rifle and some traditional ammo will do the job fine. Leading off from the previous statement, even if such projects were successful, there is a strong point to be made that, as least as far as infantry weapons are concerned, chemical-based firearms will remain both cost effective and lethal enough to last at least another century or two, if not longer.

Types of firearms

Having been around for well over 1500 years there have been many types of firearms over the course of time. Humans are, if anything, very inventive when it comes to coming up with new and interesting ways to kill each other. A rough list are:

Ye Olde Gonnes

• Handgonne: A catch-all term for a primitive guns gun without a lock that need their powder charges. Majority of these guns were handcannons, as in literal man-portable artillery pieces that had a 50/50 chance of either working or malfunctioning, the worst of which would be the gun exploding in the shooter's face.

• Arquebus - A basic matchlock Firearm. A note of clarification: 'Arquebus' and 'musket' are both used to describe firearms from this time and they are often used interchangeably. But if you want to be really technical in this period an Arquebus is a regular two handed matchlock firearm while a musket is a larger heavier gun firing a larger projectile, sometimes up to an inch in diameter. Latter (about 1700 onward) musket would refer to any muzzleloading long barreled handheld firearm used for mainly shooting solid shots. This is not too much of a big deal and is nothing to get mad about, but it is worth noting.

• Musket - Today, the musket is a catch-all term for all early smoothbore, shoulder-fired, muzzle-loaded firearms. Technically this isn't the case, the musket was an improved Arquebus, one of the earliest muzzle-loaded guns. However because of romanticism and literature; people who aren't acquainted with firearms will commonly refer to any muzzle-loaded long weapon as a musket (about the same reason why most people today refer to any automatic weapon as a machine gun). Muskets were inaccurate as people have yet to put serious research into firearm ballistics, generated a lot of smoke due to primitive gunpowder mixtures, and were temperamental to environmental conditions (rain will pretty much render a musket into an wet stick of wood), but still enjoyed a lot of popularity due to their lethality and ease of use compared to other man-portable ranged weapons at the time. The earliest versions used matchlocks, which fired by poking a slow-burning fuse into the firing chamber. Because these fuses were unreliable, they were eventually replaced with flintlocks, which ignited by generating sparks in the firing chamber. Muskets were quickly phased out once rifles became a feasible thing, who did what a musket could, but better.

• Multi-barreled gun - In the olden days, people wanted shootier guns but things like magazines and self-loading weapons were still an alien idea during its time. So as an alternative people took a breach/muzzle-loaded firearm, slapped one or more barrels onto it, and reworked the trigger so they can fire more shots before needing to reload. This resulted is some particularly wacky times for guns. To this day, the only multi-barrel weapon still commonly used (disregarding military rifles with underslung grenade launchers, door breaching shotguns, or rotating barrel Gatling-style guns) is the double-barreled hunting shotgun.

Modern Firearms

• Handgun - Also called "pistols", handguns are small-sized firearms that can be comfortably fired in one hand (hence the name). Handguns are mainly used for close defense and as a sidearm, making them akin to daggers. Modern pistol calibers are commonly between 9 and 11mm, although popular magnum rounds like the .357 magnum and .50AE are also common for handguns (albeit they tend to be large and heavy).

• Machine pistol - A machine pistol is a handgun that can fire on full auto. While they're commonly thrown into that category; machine pistols are not submachine guns due to their size and use. They are not as popular as they used to be seeing how Personal Defense Weapons are filling the niche they once did with more firepower.
• Derringer - A tiny pocket pistol. These things have been around since the 19th century. Often used as concealed or personal defense weapons, these things could fit into the palm of your hand and were single-shot, though could have two barrels. Not all derringers use weak rounds, either; at least one modern design manages to pack four .357 magnum rounds.

• Revolver - A revolving gun is any weapon that uses a revolving cylinder to load new rounds after every shot. While its commonly now relegated to pistols (a revolver typically meant a revolver pistol these days) the style is still used for some shotguns (like the Armsel Striker) and grenade launchers (like the MM1-Hawk). Revolvers are still in use for a few reasons: they're simple and cheap to make, can easily be used by left and right-handed shooters (since spent casings aren't automatically ejected like in the case of modern firearms) and is still pretty robust compared to today's modern weapons as fewer mechanisms means fewer points of failure. Downside is that they have very limited ammunition space (because the gun was made around the cylinder you can't expand it like how you can with detachable magazines, so you either had a gun with 5-8 rounds or a bulky gun with a 12-round cylinder) and reload time (revolvers in all generations were a pain in the ass to reload. If you had an old revolver with a loading gate; you had to eject each round by hand, then load new rounds. If you had a newer one; you had to empty the cylinder, load the rounds, then cock the hammer. This is in contrast to modern guns where you just had to eject the magazine, load a new one, and charge the weapon). "Snubnose" revolvers refer to revolvers with shortened barrels in an attempt to make them more compact. Thanks to the American old west era and subsequent movies about it; revolver-styled handguns have achieved a kind of rustic yet sleek appeal to them. Revolvers come in generally the same calibers as handguns, from the modest .22 Long Rifle used for practicing and target shooting to the behemoth .500 S&W Magnum which can put down a bear.

• Submachine gun - A submachine gun (abbreviated to SMG) is a fully automatic weapon that fires pistol cartridges instead of the larger rifle cartridges. One of the first true fully automatic infantry weapons outside of the machine gun; the weapon fulfills a similar role of the carbine in that its a weapon made for infiltrators and assault units as its compact size and power makes it a close-range powerhouse. They also make good stealth weapons, as its easier to suppress the noise of a pistol cartridge than a rifle cartridge (as most pistol rounds are subsonic).

• Personal Defense Weapon - A PDW is a bit of a mix of a carbine and an SMG, firing specialized cartridges with rifle-like characteristics (usually in the 4-5mm range, shorter than a rifle cartridge but longer than a pistol cartridge) at the cost of additional weight. Its original role is as its name implies; a personal defense weapon for nonfrontline infantry, like artillery spotters, scouts, vehicle crews etc. Back in the day PDWs weren't necessarily automatic; a pistol with a longer barrel and mounted stock could be classified as a PDW (This was done with the German C96 and Luger P07). These days PDWs are commonly lumped into the same category as SMGs, as they now fulfill similar roles.

• Shotgun - Shotguns are smoothbore weapons (as in the barrel is not rifled) designed to fire either shot (multiple steel or lead pellets) or slugs (a single, heavy projectile), although modern times have included other types of ammunition. The ability to fire multiple types of ammunition without modification is one of the main advantages to using a shotgun; converting an anti-infantry weapon into a door-breaching tool, a mini-flamethrower, or a non-lethal weapon with but a switch of the munitions. The vast majority of shotguns are pump-action or breech-loading, though military shotguns can come in semi-automatic or fully-automatic configurations. For more information see the shotgun page.

• Rifle - Rifles were originally shoulder-fired weapons that had their barrels "rifled" to increase precision, which was an act by putting spiral grooves into the barrel in order to have the bullet spin before leaving the barrel. However, because most modern firearms now use rifling to improve ballistics; a shoulder-fired long weapon, designed for accurate fire is usually classed as a rifle.

• Assault Rifle - Assault rifles are a term given to any rifle that can be fired on full-auto and shoot intermediate-caliber rounds, typically in the 5mm range (or a shortened 7mm round if you're from the Eastern bloc). This is usually the standard weapon of a non-specialized front-line infantryman.
• Battle Rifle - Basically a bigger assault rifle; battle rifles are bigger automatic rifles designed to fire high-caliber rounds, typically in the 7mm range. These were the mainstay for armies in the 1950s, but the US eventually found out that giving infantry rifles with smaller rounds is better since its lighter and can allow infantry to be more accurately engage enemies better due to lower recoil (albeit at the cost of power), so battle rifles were replaced by assault rifles for front-line use and battle rifles were relegated to specialists like marksmen or support gunners (who's job permits for a slower-firing but more powerful weapon).
• Carbine - A carbine is a compact rifle, primarily designed to be used in close quarters. In most cases, carbines are based from a parent assault/battle rifle, and are scaled down by using lighter/smaller parts and shortening the barrel (such as in the case of the American M16 and M4) or is its own weapon (like the Korean K1A). These are typically given to units who need to engage the enemy at close range and need a rifle for the job, like commandos, assault teams, or other specialist units, or given to units who are not expected to fight on the front but need a compact but decent weapon to defend themselves if the need arises, like pilots or vehicle crews. Carbine may also refer to pistol-caliber semi-automatic weapons that are longer than a pistol, but this is typically only used in the civilian market.
• Micro Assault Rifle - Even smaller than carbines; these are ultracompact rifles designed when someone needs a highly portable but powerful weapon. A MAR is basically a PDW that shoots actual rifle rounds. Much like carbines; a MAR can either be based on a parent rifle and scaled down or made as its own weapon.
• Sniper Rifle - A sniper rifle is a special precision rifle, specifically designed to engage targets at extreme range with lethal efficiency. Many sniper rifles use standard 7mm rounds, but high-performance rifles will use magnum (extra-power) rounds or 12mm rounds for extra range and stopping power. The vast majority are bolt-action for simplicity and power (much more reliable and because all the gasses are diverted into the barrel, rather than some being diverted to work the action; the gun can launch the bullet farther and faster), but there are also a decent number of semi-automatic ones. Sniper rifles are given to special marksmen called "snipers", who engage the enemy from very long distances, usually well away from the scrap.
• Designated Marksman Rifle - A sort of compromise between battle rifles and sniper rifles, DMRs are precision weapons meant to be used by frontline infantry to accurately engage distant targets that regular infantry weapons cannot. Due to its role; it's more accurate than a rifleman's gun, but not nearly as effective as an actual sniper's gun (DMRs are usually only effective within 1 kilometer, while SRs are typically effective beyond 1 kilometer). Generally speaking, DMRs never use high-performance rounds that snipers may use, as it would be excessive for their role.
• Recoiless - Not a conventional gun in most senses; a recoilless gun (models with rifling are called "Recoiless rifles" though people often miss this distinction) is as the title suggest, a rifled weapon without (or at least reduced) recoil. It does this by basically being a cannon with the back taken off. When loaded the cartridge sits in an open back tube, there is no breach. When fired, the explosion propels the shell out the tube, but an equal amount of gas comes out the other side canceling out the recoil. This means that total muzzle velocity is lower than a cannon with a breech on it, but they make up for it by shooting bigger shells, and with HEAT shells (thanks to the nature of the Munroe effect) the wider the diameter of the shell the more effective it is, meaning even a large slow moving projectile can do a great amount of damage to tanks.
• Anti-Tank/Materiel Rifle - Essentially modern elephant guns; these rifles are geared towards destroying tanks and hard objects, although they are very much still capable of demolishing infantry (albeit overkill since rifles of this type tend to outright cause body parts to explode by the sheer amount of force they carry.). Anti-tank rifles were the norm for years (From the 1910s to the late 1970s) as they were a cheap yet effective way of getting rid of tanks, but advancements in vehicle armor has largely rendered AT rifles obsolete (although they're still very much capable of penetrating light vehicle armor). Anti-materiel rifles however, are a bit of an offshoot of AT rifles, and are still in use today.
• Everything else - All of the above rifles are "military-grade" and thus are generally not available to the public (unless you are in America, see NFA for detail). Any other type of rifle will typically be called a "sporting rifle" or "hunting rifle", etc and are either bolt-action or semi-automatic.

• Machine Gun - Colloquially a machine gun is a large automatic weapon (though technically anything fully-automatic, ranging from a machine pistol all the way up to auto-cannons), typically fed from a magazine or a belt and meant to either be portable or fired from an emplacement like a tripod or turret. The main difference between MGs and the rest of the automatic weapon family is that an MG is a gun meant to fire with longer continuous bursts as a support weapon; meaning that the machine gunner stays back to continually shoot at the enemy to keep them down (and occasionally kill those stupid enough to not get the message), while the rest of the squad maneuver. Machine guns are generally heavier, not only because of the volume of ammo they carry; but their parts (such as the barrel) are made of heavier materials so that the gun can withstand the punishing amounts of bullets it puts downrange (firing hundreds of rounds without pause can cause guns to overheat and malfunction, even catch fire or explode in the worst of scenarios, unless they're built for such a task.)

• Light Machine Gun - an LMG is a man-portable MG that fires the same intermediate rounds as assault rifles. They are intended to be almost as portable as a rifle (as in, they can be shouldered, but get better performance with a bipod) and allow machine gunners to provide suppressing fire at the squad level. Some LMGs are magazine-fed rifles with heavier barrels and modified bolts (such as the RPK), or else scaled-down MMGs (such as the M249 SAW).
• Medium Machine Gun - an MMG is a man-portable MG that fires the same full-power rounds as battle rifles. These tend to push the limit of what's practical for a man-portable weapon, and when deployed are usually fired from a stationary position either on a bipod or tripod due to the recoil they generate. These weapons are more multi-role and tend to be deployed at the company level or as a vehicle weapon.
• Heavy Machine Gun - HMGs fire large caliber rounds (like the famous .50 cal). Unlike the other two; HMGs are exclusively meant to be fired from emplacements like a tripod due to their large size and weight, which makes them impossible for an infantryman to fire on the move, unlike the light and medium machine guns. HMGs are powerful enough to penetrate light armor, making them a formidable weapon.
• General Purpose Machine Gun - Essentially a machine gun that can perform multiple roles of the previous stated. The M240 is one such gun, and modifications and variants lie out there that make it relatively light for a machine gun.
• Rotary Machine Gun - Originally known as the "Gatling gun", man's first known attempt to have enough dakka; a rotary machine gun is an automatic weapon that uses revolving barrels that interchange every time the gun fires off a round. The kicker to this is that it allows the gun to shoot with little threat of the barrels wearing out as they interchange between shots; giving them a small window to cool off before firing again. The end result is a gun capable of firing over 3,000 rounds per minute without fail, or in a smaller scope; 50 rounds per second. Modern rotary guns are electrically powered to allow them to reach such insane speeds, and are given ammo drums that contain thousands of rounds to be able to sustain that amount of bullets being fired; so they're confined to static emplacements and vehicles (unlike what the media constantly portrays; these things are not even close to being man-portable without assistance from powered armor.) These types of guns are used almost exclusively on aircraft or anti-aircraft emplacements, as they're the only non-missile weapon that can reliably hit fast-moving aircraft. But a rotary gun that fires 30mm rounds is powerful enough to tear tanks in two, as well (metaphorically, they only have to penetrate top armor and rate of fire helps). Unlike what the movies would tell you a rotary machine gun does not need a long spinup time to get to full speed: when the trigger is pulled the gun starts to spin and fire immediately.
• Chain gun - A chain gun is a machine gun that is fed using an electric motor. Instead of relying on the gasses from the bullet to work the action to cycle a new round; a machine automatically ejects and loads a new round in after firing a shot. Chain guns have the benefit of never jamming due to feeding failures, as even if the round is not discharged; the machine pops it out and loads a new one regardless. However, it is also not man-portable as it requires an electric motor to function, so it is only found on fixed emplacements or vehicles.

Actions

"Action" refers to how ammunition is loaded into the weapon.

• Single-shot: The first and oldest of all; a single-shot weapon is when users manually load rounds into the chamber. This can be anything from loading a new round, cocking the weapon every shot, or pumping the action.
  • Muzzle-loaded: The earliest form of how weapons were loaded. This meant you had to load a new round directly into the muzzle, which is where the bullets come out. In its earliest form; muzzle-loaded guns were complicated to arm; you had to fuck around with a wad, powder, and slug. In the heat of battle, you had to ram these down the barrel of your gun in the correct order, light the wick, then aim before the gun goes off. And you had to do all this while standing in the open within firing range of your enemy.
  • Breach-loaded; An upgrade over muzzle-loading and developed shortly after cartridges were invented; breach loaders are where the bottom of the barrel can be unhinged so that you can load a new round into it. It is still a popular setup for multi-barreled shotguns. Certain revolvers are breach-loaded as well, but given the size and design of the revolver, this gives them a notable weak point at the top of the weapon where the parts connect together.
  • Bolt-action: This type of action is where you pull the charging handle of a weapon, every time you shoot so that the mechanism would chamber a new round. These were pretty popular in WW1 and continues to be used today for precision rifles.
  • Lever-action: The cool kid of the single-action club; lever-action weapons are those where you have to use a lever to chamber a new round, which was usually mounted near the trigger. This type was made popular by Winchester during the frontier age of the Wild West and even more by Arnold Schwarzenegger when he used a lever-action shotgun during Terminator 2.
  • Pump-action: A pump action is where you had to pull the "pump" of the weapon to cycle a new round. This is the most common action used by shotguns. A few rifles used this setup as well, and there is one instance of a bunch of madmen creating a pump-action 3+1 (three in the tube, one in the chamber) 40mm grenade launcher.

• Semi-automatic: A semi-automatic weapon is any weapon that can fire after every trigger pull, with the user only needing to work the action after reloading a completely empty gun. Unlike single-shot weapons, it uses gasses expelled by the cartridge or recoil to power a mechanism that automatically chambers a new round after each shot. Most handguns and many rifles are semi-automatic.

• Burst-Fire: A setting sometimes included on automatic weapons, each trigger pull fires three (or sometimes two) rounds in rapid succession. This is used as a way to allow automatic capability without wasting bullets, as keeping the trigger held too long on anything other than a mounted weapon tends to cause it to lose accuracy very quickly.

• Fully-automatic: A fully-automatic weapon is any weapon that can fire automatically, so long as the trigger is depressed, rather than pulled each time like how semi-autos work. Automatic weapons tend to be banned for civilian use and are only available to military.

Ammo Storage and Feeding

This refers to how ammunition is given to the weapon. Also the topic of a /k/ommando's greatest sources of rage; the clip vs magazine misconception. This section will give a short explanation for both.

• Pepperbox - used mostly in the days of the muzzle loader a pepper box has multiple barrels loaded and ready to be fired. The Empire's Outriders are armed with these weapons if you want a visual of what they looked like.
• Superposed load - the disadvantage to using a multi-barreled firearm is that it adds a lot of weight to the firearm. One alternative was to simply stack multiple bullets and charges into the same barrel, and then have the firearm set them off sequentially. The early version of this mechanism was prone to failures, as the bullets were not self-contained and a poor gas seal could result in multiple charges going off, exploding the barrel. However, this setup was revived with the invention of caseless bullets and electronic triggers used most prominently in Metal Storm weapons. If combined with multiple barrels, a metal storm weapon can have a bewildering rate of fire. So far the technology is mostly used in multi-shot grenade launchers.
• Clip - A clip is a device, used for bundling bullets together for immediate use. Guns cannot use clips by themselves, they have to be loaded into a magazine first to be used by a gun. The most common version were "stripper clips": each clip held about five bullets, and to load the rifle you placed the clip on top of the magazine, then squeezed the bullets off the clip into the magazine. Another type, en bloc, was used by the M1 Garand and held eight bullets in a 2x4 configuration. The entire clip was put in the magazine, with the clip being ejected after being emptied. The last kind is the moon (or half-moon) clip, used specifically for revolvers, which holds bullets in a circular formation for loading the chamber up in one go.
• Magazine - The magazine is part of the weapon that houses and feeds actual ammo into the weapon. In the olden days, many guns had magazines that were built into the weapon itself and were fed using clips of ammo that were loaded after the gun ran out of ammo. Built-in magazines, however, severely limited the potential ammunition capacity of guns as they cannot be expanded without significantly making the gun larger and was a pain in the ass to reload (such as in the case of revolvers). To counter this; people designed guns whose magazines were detachable from the gun itself. This allowed people to easily expand the ammo cap of a gun by just making the magazine bigger and made it easier to reload ammunition (after all if you're reloading a gun with 30 rounds; its much faster to just load an entire mag than cramming 30 rounds worth of clips down it). High-capacity magazines tend to take on weird shapes rather than the standard flat box; the most common variant is the drum magazine, but there are also double drums, caskets, and helicals.
• Belts - The belt is what it is; a long belt filled with bullets, which can either take the form of a cloth belt or linked by metallic chains. Belts are the common loading method of most machine guns, who typically have ammunition capacities well beyond 100 rounds.
• Bullpup - A bullpup is any weapon where its action is located in the behind the trigger, instead of in front. Bullpups have the advantage of being more compact, compared to the traditional setup, as most of the gun's mechanism is located in the stock area. but has the disadvantage of not being ambidextrous (being that the shell ejection port is directly beside the shooter's face, left-handed shooters are forced to shoot from the right to not get their faces burned off) unless specifically designed to be so. This is usually resolved by cutting out ejection ports on both sides and swapping parts over, or else ejecting bullets downward or forward.

Relations here

Most fantasy writers tend to exclude firearms. There are a variety of reasons for this, such as:

• Most fantasy comes from Tolkien, who, being a naturalist who largely despised industrialization, did not put guns in Middle-earth, although gunpowder does exist, used by the wizards (Gandalf's Fireworks and Saruman's Fires of Orthanc) and by the orcs.
• Most fantasy (whether copy-catting Tolkien or not) is based on medieval Europe. Depending on your definition of "medieval," Europe did technically have firearms towards the very end (crude and unreliable ones, but firearms nonetheless), but most authors base their fantasy on earlier medieval Europe.
• As in real life, firearms mean that vulgar, dirty, peasant conscripts can take down the author's Mary Sue noblemen knights that trained so hard in the arts of swordsmanship and melee combat, though if the writer had any historical knowledge they would know that armor can be made "Proof" against bullets, which is partly what spurred the development of full-body plate mail, to begin with.

All that being said, most fantasy authors are much more open to cannons, which became viable on the battlefield long before smaller firearms anyway.

Generally speaking, if a world has both the "stock" fantasy races and guns, there will a strict hierarchy of who uses them, from most to least likely:

• Dwarves: They almost always have the best, most plentiful guns. If only one race gets firearms, it's likely going to be them.
• Gnomes: As tinkerers, they're frequently on a different tech level from everyone else, including firearms.
• Humans: Unlike the other races, which are usually an all-or-nothing deal, different human nations have different likelihoods of having guns. Italian and East Asian analogues, as well as the "industrious" or "scientific" nations, are much more likely to have them. Your barbarians, guys keen on knights and chivalry, and the more conservative less so.
• Orcs: Orcs would probably love guns if they could actually build some. However, they're usually either incapable of building things or have a hard time organizing themselves to the point that large-scale firearm and powder production is possible. Even so, they could still obtain them them by other means such as fighting as mercenaries for guns and stealing them off the corpses of the fallen and similar. They are higher on the list if they are more like Tolkienian orcs, which can be fairly well organized and "delight in explosions" enough to manufacture their own gunpowder, if only for simple bombs.
• Elves: Being arrogant pricks, they see guns as crude, inaccurate, foul-smelling contraptions that are no substitute for a bow. However, they'll still use them when necessary, even if they don't like it. That said, elves also had a good reason to not use them, namely most firearms in a fantasy settling are arquebus-type single-shot smoothbore weapons, which are outranged by longbows. Longbows are even decent against most kinds of armor (ask the French). The main advantage of firearms, even early ones, is ease of use and armor penetration though armor could be made that could stop an early handgun. The main problem with longbows is that it takes years to learn, which is not a problem for long-lived elves. Between a smoothbore handgun and a longbow, the bow is simply a better choice to an elf. The problem of course is that longbows are about as good as bow technology can get while handguns can be improved to rifles, against which bows only have rate of fire as an advantage, then Repeating Rifles, which bows have no advantage at all against. So while Elves may have an advantage to sticking with there longbows well into the age of pike and shot, if there not careful there Longbows will end up fighting against Springfields and Winchesters and they will end up the worse in that exchange.
• Wood Elves and other Fey/Nature types: They'd rather die than use a firearm, even if the rest of the world has moved onto biplanes, bolt-action rifles, shell-firing cannons, and tanks. If this happens, this means they either have powerful magic (so the actual weapons used are unimportant), they are really really good shots with a bow, they have much stronger friends (Think like the amish) or they're about to die out. That said: the problem they have are not guns themselves, but making them as mass production always has some environmental costs they can not stand for. If they could get there hands on some way to make guns that did not harm the environment in the process, at least anymore then making a sword does they might go small for small scale fire arm production, but this is rarely explored in fiction.

For how this conservative attitude tends to apply to tech in general for fantasy settings, see Medieval Stasis.

Of course, sci-fi writers almost exclusively use firearms, seeing as how it's THE FUUUUUUTTTTTUUUUURRRREEEE. The exceptions are Warhammer 40,000 and Dune: although guns are the main combat implement in 40K, close combat is still alive and well, and most armies have at least one elite, close-combat unit wielding weapons that are distinctly not firearms; in Dune, guns are pretty much dead as a weapon of war, as personal-scale force fields stop fast-moving matter (like bullets) from crossing them, but slower matter (like swung knives) can pass through, and if a lasgun blast touches the field, at least one end of the equation comes out "BOOM!!!". Most sci-fi universes do have close combat weapons on the scale we see in modern warfare, though, like in Mass Effect, where, as the Reaper forces (who are basically Necrons and Tyranids combined) invade the galaxy, people begin developing their Omnitools to snap-produce a white-hot blade of hard metal above the wearer's hand... And then there's the Krogan, who are too bloodthirsty and too large to properly take cover, so they headbutt things instead of using guns.

Rules

Most fantasy RPGs deal with firearms the way they deal with lots of things that threaten their Medieval Stasis: terror, suspicion, and shitty rules. If you have the option of using a firearm in most games, it probably has one shot that's weaker than a bow, then takes an entire encounter to reload, and is illegal everywhere in-setting in case you didn't get the hint.

BECMI Dungeons & Dragons doesn't have rules for firearms, but there were one or two adventure modules that incorporated a crash-landed spaceship, with weapons the players could loot. They were treated as magic wands and staves. A few issues of Dragon magazine offered rules for early cannons and hand cannons.

Advanced Dungeons & Dragons mentions guns in a tucked-away subsection on importing TSR's Cowboys & Indians game Boot Hill to AD&D (DMG, pg113). Revolver pistols and Gatling guns would do as much damage as a longsword; shotguns as much damage as a two-handed claymore, a (thrown) stick of dynamite does 4x the damage of a short sword. The rules insist "...when gunpowder is brought into the fantasy world it becomes inert junk, ergo, no clever alchemist can duplicate it." To reinforce this concept, the Manual of the Planes included rules for factors of prime material planes, one of which determined if complex (read: setting destroying) chemical compositions like blackpowder would even work in said plane. If you have any knowledge of chemistry, you may cry now. Notably, Greyhawk had a god of firearms, and his paladins were basically Wild West sheriffs.

Advanced Dungeons & Dragons Second Edition included the arquebus in the Players Handbook, where they were depicted as slow, powerful and expensive (500 Gp!). They were also potentially dangerous to the user as the result of a bad roll. It was painfully stressed that the inclusion of firearms in the campaign was the call of the DM. Firearms were a bit more common in the Spelljammer setting. Moving away from the classic fantasy background, there was the historical campaign sourcebook A Mighty Fortress that introduced rules for firearms of the 16th and 17th centuries and the Masque of the Red Death setting for Ravenloft pushed everything into a gothic horror version of the 1890's.

D&D third edition has a section on advanced technology (DMG, pp162-164) for Renaissance-era, 20th century, and futuristic weapons. The weapons are more powerful than what can be found among ranged weapons in the Player's Handbook, but also heavier and more expensive. You're better off with magic crossbows.

Pathfinder seems to do early firearms right: they have shorter range than bows without magical items, take longer to reload, have a chance to break or explode on a misfire, and use up more expensive ammunition, but they hit harder, have a terrifying 4x crit modifier, and use touch AC in the first range increment, effectively ignoring armor when fired close up. Probably the only things restricting their use so heavily are the stiff feat tax needed to make use of them and the fact that there's really only one major gun factory in the land, the Gunworks of the small nation of Alkenstar, and they keep most of their guns to themselves. A specialized class, the gunslinger, is centered around the use of firearms.

Dragonmech has guns, sort of kinda, as well. Only instead of using gunpowder, they use steam to propel the bullet like an airsoft gun. they can only be fired once every other round as the pressure needs to build up. There Treated a bit like crossbows that do more damage and can shoot a little further.

Dungeons & Dragons 5th Edition includes a section on firearms in the Dungeon Master's Guide. They hark back to 2nd edition in terms of stats, fitting the general tone of the game, but aren't quite as punishing for a player to learn to use and make. And with the increased emphasis on houseruling and homebrewing, modding the Crossbow Expert feat to work for them seems a simple leap of logic. The "race builder" guide in the back even suggests changing around the dwarf weapon proficiencies to include them! Furthermore, if you want to get your Expedition to the Barrier Peaks on, it includes some futuristic guns as well, like lasers and disintegrators.

Medieval Weaponry
Melee Weapons:	Battleaxe - Dagger - Lance - Mace - Club Pole-arm - Spear - Sword - Warhammer
Ranged Weapons:	Blowgun - Bows and Arrows - Cannon Crossbow - Firearm - Rocket - Shuriken - Sling - Incendiary Weapons - Artillery
Armor:	Armor - Fantasy Armor - Helmet - Pauldron - Shield