• 14th century is a time, not a place. 14th century China, 14th century Ottoman empire, 14th century Muscovy, 14th century France and 14th century Inca empire are not at all the same thing.




• Let's see what they didn't have in the 14th century anywhere. No steel in quantity, and no capability of making steel with consistent properties. No reliable steel springs. No propellant suitable for machine guns. No reliable primers. No notion of mass production -- a Madsen machine gun fires 450 rounds per minute.




• Most importantly, they did not have the capability of expressing the dimensions of the parts and ammunition with anything near the required accuracy. I'm not speaking of making them; they literally could not express them. The size of an inch varied greatly from place to place, and from generation to generation.




• So you want a (presumably Western European) 14th century with the capability to make steel in quantity, with machine tools suitable for machining steel, with advanced chemistry to make propellants and primers, with uniform units of measurement, and with an industrial base capable of mass production. All right, but then what has this fantasy in common with the 14th century? How do you intend to reconcile late 19th century industrial base with a Late Middle Ages social structure?

No.

Not in the way that you're looking for, at least.

Put simply, cartridge fed weapons aren't products of metallurgy, they're products of precision and mass manufacturing. In something like an AR15 (or any rotating-bolt action, really), if the round is slightly out of tolerance and doesn't fit in the chamber properly, the weapon can explode. For a less catastrophic example, if the feed lips on a metal magazine are slightly bent out of shape, the weapon will constantly misfeed and jam - not something suited for a machine gun.

Any firearm built in the last hundred years operates on the following assumption: Every round fed to it is exactly the same. They're wholly reliant upon mass and precise manufacturing of ammunition. A few thousandths of an inch here, or slightly more or less powder there, and the weapon will lock up, stovepipe, squib, double feed, detonate, or otherwise fail in its intended purpose.

The level of precision to mass-manufacture cartridges is simply not possible with dark-ages craftsmanship.

You're gonna have to figure out something else

Here's an idea - what about some kind of gatling-flintlock? A hand-cranked mess of gears and pulleys that loads ball and powder into a barrel before passing it over a candle to fire. Not exactly an infantry weapon, but I could see something like it atop a horse drawn carriage.

You could also dream up a breech-loaded musket, fed with a lead ball and pre-measured bags of powder. By no means a modern rifle, but it'd still be significantly quicker to load than firearms of the day. Draw inspiration from a modern bolt-action, perhaps.

Look at modern guns and ask yourself "How would I load marbles and sand into this?" That should help you design your medieval wonder-weapon.

Depending on the needs of your story, you might consider...

The volley gun: A bunch of single-shot guns joined together. According to HyperWar designs like this appeared as early as 1339, and that drawing is by Leonardo da Vinci. You can see a modern reproduction of such a gun being fired here.

Historically, volley guns would fire all their rounds at once, but there's no reason you shouldn't have a handle you turn or a special fuse to fire them one after another.

The advantage of this is you can take real historical gun technology from the era you like, and just say a bunch were joined together.

The downsides are probably obvious: Weight and reload time. You're not going to see soldiers carrying around a 20-barrel gun any time soon! But if you only need short bursts of fire and don't mind needing a horse and road to transport it around, it could be an option.

There's also a design of gun where multiple bullets are loaded into the barrel at once, then fired in succession, like a roman candle - a so called 'superposed load' which Wikipedia says was first described in 1558. Never really caught on as it's difficult to make it work at all, let alone make it easy to reload in the field, but if your plot calls for occasional hails of bullets and you don't mind applying some artistic license, you could claim the problems were resolved because your fictional world has different powder chemistry or something.

Alternately, if all you want is battlefield weapons that will give a squad of men a chance of being wiped out in seconds by a handheld weapon, you might consider the hand grenade (震天雷, 1044 AD) or the flamethrower ('greek fire', 672 AD) (although I don't know how easily portable the latter was in pressurised form)

To make a machine gun you need to have already developer breech-loading.

Although breech-loading firearms were developed as far back as the late 14th century in Burgundy, breech-loading became more successful with improvements in precision engineering and machining in the 19th century.

The main challenge for developers of breech-loading firearms was sealing the breech. This was eventually solved for smaller firearms by the development of the self-contained metallic cartridge. For firearms too large to use cartridges, the problem was solved by the development of the interrupted screw.

Also in the 14th century you would hardly have the manufacturing control capabilities to ensure narrow enough production tolerances, needed for producing the bullets and the mechanical parts. And you would also lack the needed good quality materials.

This all depends on what you mean by a machine gun. The heart of a light machine gun is its ability to use recoil energy to load the next bullet from a collection of bullets. However, there are other ways to achieve that rapid firing effect. A 19th century double action revolver handgun can be fired rapidly by using the non-aiming hand to fan the hammer into the cocked position. An expert can shoot that revolver faster than a modern semi-automatic handgun. Also, the auto-loading feature relies on a certain range of pressure, so a revolver can actually be chambered for more powerful (i.e. faster and more lethal) hand-made rounds than a semi-automatic handgun.

The real problem is the ammo, machine guns in general are relatively simple and people were able to make them out of some pipes in their back yards, so any society that can make metal springs and tubes theoretically can make a machine gun.

However, it would never occur to anyone as a practical idea unless there is an industrial scale production of cartridges, as they have to be exactly the same size-wise to load properly, so making them by hand is highly unlikely to be practical. Even if you have a large group of very precise workers there is still the issue of propellant. Smokeless powder was only invented in late 1800s and required a number of other chemical advancements to become possible. Before that black powder was used. Black powder is pretty unusable for automatic weapon, as it will gunk up your weapon real quick, and fill the area with so much smoke you wont see anything after a few shots.

So the ammunition is the limiting factor not the weapon itself

no, machine guns were invented in 1884. If you want to learn more about the machine gun I highly suggest
https://www.history.com/topics/inventions/firearms
or
http://www.pbs.org/opb/historydetectives/technique/gun-timeline/
it is about the history of firearms.
Although machine guns weren't invented gunpowder was available.
1364 is when the first use of a fire arm was recorded
1380 is when handguns were available across europe
1400 matchlock gun
1498 rifling principle is discovered
1509 invention of wheel lock

No, but.

There were guns built in the 17th century, which would have been (barely) with the capability of 14th century (Western European) handgonne makers, that approximated a short burst from an automatic weapon.

I speak, of course, of the "volley gun". These consisted of a number of gun barrels mounted parallel to one another (in what amounted to a sturdy rack, generally on a wheeled cart due to weight) -- anywhere from six to thirty-two barrels that I know of, though there may have been guns with more. The barrels were all loaded with powder and shot (either a single ball or small shot), and a powder train in a trough was used to ignited the barrels in rapid sequence. This amounted to nearly an hour of loading time for a single burst of fire that took anywhere from two to perhaps ten seconds (depending how fast your powder train burned).

Volley guns were effective, but limited -- they laid down a withering fire, similar in effect to grape shot from a cannon or a canister round, but with less spread. Tactically, they'd be treated as a very heavy shotgun. The limitation was, they were very much a "fire and forget" weapon unless used in specific applications, like defending a wall, where the enemy couldn't just overrun the gun after it fired. They didn't catch on because grape shot, canister, and shrapnel were at least as good and much faster to load once cannon were common.

All questions about "could they have had X in medieval time". Nicely forgets one important bit of secret sauce.

Before the enlightement, we had not discovered that we didnt know most of the things. Simply in the worldwiew was that everything important was known. While some uninportant things were left unknown, the big picture was more or less there. They didnt have the mindset needed for R&D, they didnt have the social structure for it either.

It took us a very long time to come to diseminate the attitude that we can do things better if we try. Even today the social fabric is more in the way of changes than the actual changes themselves.

So no they could not have done it. They hadnt invented standardisation, tolerances, interchangeability and the modern metal lathe. With those inventions the might have been able to but then interchangeable parts was a Huge invention.

Its not that they could only maintain a few guns they couldnt supply the gunner with ammo since they would need thousands of peoples yearly output to make the ammo for a single battle.

The question title states 'could machine guns be produced in the 14th century' it then goes on to confound itself in the body of text. A modern weapon could not be made by a 14th century nation.

Casting (and thus relative uniformity of production) existed well before the Industrial Revolution though, certainly using different moulds would produce different results, but ammunition could be sorted by hand post-production readily enough, it wouldn't even require any expertise.

One does not need exact measurements nor modern reliability to create a 'machine gun.'

Steel is not required to produce good springs.

Steel is not required to make cartridges.

Steel is not required to produce guns.

Perfectly reliable charges are not required to make good weaponry.

Automation was a known concept, numerous examples exist of it, from clockwork mechanisms to spring powered saws.

From Wikipedia - "Up to the 15th century, clockwork was driven by water, weights, or other roundabout, relatively primitive means, but in 1430 a clock was presented to Philip the Good, Duke of Burgundy, that was driven by a spring."

That is not to say the metal spring was not invented until the 1430

From Wikipedia Torsion springs consisting of twisted ropes or sinew, were used to store potential energy to power several types of ancient weapons; including the Greek ballista and the Roman scorpio and catapults like the onager.

https://www.ideaconnection.com/right-brain-workouts/00346-who-invented-the-toothed-gear.html

1836 Colt and his revolver. Such a miraculous invention.. with the use of a spring and a ratchet..

https://www.youtube.com/watch?v=hiFGKWPSaas

https://www.youtube.com/watch?v=Ycyj76VPOtc

The mechanical concepts (and even the parts) required to build a machine gun had already been demonstrated long before the creation of what people recognise as the first automated weaponry.

I think the only part of a machine gun that could not have been readily be designed by a 14th century artificer is ammunition of any reliability, but that needn't kill the project if a part of the automation process expelled failed or partially failed cartridges without relying on the power provided by a spent round.

there is no need for an automatic weapon to fire quickly in order for it to be classed as a machine gun, nor is a rof of 400 or more rounds a minute in any way feasible imo.

A 1300s machine gun would probably make use of a secondary, manually empowered spring prior to contact to act as a guarantor of motion, any failure to fire being catastrophic(which is likely a primary reason why the gatling gun wasn't automatic)

Something like a maxim, but instead of striking a cap a fuse is lit in the rear of the casing with a delay charge, arranged such that perhaps cartridges are lit with a fuse of ~1s.

That is, the fuse is lit prior to the the rotational point of chambering and firing, the last 3 rotational points are inside a secondary (ignition) chamber aligned on the ammunition's arc such that debris from the fuse's ignition can be cleaned out in a separate, external part. This 'external' arc is open to the air forwards, allowing any accidental explosion or pre-ignition due to dust build-up that may occur to be directed away from the user and his allies(if not quite constituting a second barrel)

Depending on the design, the automatic motion normally chambering a round could be aligned to, say, every fourth or fifth (or less or more depending upon tolerances) fire a spring loaded wad instead of a bullet. There is after all no reason why a gun need be cleaned from the muzzle end of a breach-loaded weapon. (And the wad does not need so much strength as to hit the enemy, just to leave the barrel)

Don't really know how light such a contraption would be.

More from wikipedia -"The grouped barrel concept had been explored by inventors since the 18th century, but poor engineering and the lack of a unitary cartridge made previous designs unsuccessful. The initial Gatling gun design used self-contained, reloadable steel cylinders with a chamber holding a ball and black-powder charge, and a percussion cap on one end. As the barrels rotated, these steel cylinders dropped into place, were fired, and were then ejected from the gun. The innovative features of the Gatling gun were its independent firing mechanism for each barrel and the simultaneous action of the locks, barrels, carrier and breech.

The ammunition that Gatling eventually implemented was a paper cartridge style round charged with black powder and primed with a percussion cap. because self-contained brass cartridges were not yet fully developed and available. The shells were gravity-fed into the breech through a hopper or simple box "magazine" with an unsprung gravity follower on top of the gun. Each barrel had its own firing mechanism."

So we have here an existing weapon that uses things that were available in the 14th century, paper, brass, gunpowder, ratchets, springs, primers, multi-phase automation.

Mass production, precision engineering, chemical uniformity and quality assurance processes do not make a machine gun, they just make good machine guns.

There is a webnovel about that, entirely. The synopsis is all about bringing modern weapons tech to middle-age-like civ. For doing that there were some pre-requisites:

• The protagonist has memories of the present day, also, he is a mechanical engineer that also is weapon-addicted.


• He is a prince, not the first one in the sucession line


• He uses his knowledge of chemistry, and the local alchemists to start researching black powder and a way to mass produce it


• He start by making muskeeters (start small)


• Since he is a prince, he chose the measurement units as measures of his own body, and they were accepted


• He also start to change the mindset of people and educate them so that he can use them in factories


• Mostly, with his previous knowledge, he researches most of things that is missing


• He does all of this in some years


• The setting is in a fantasy world pretty similar to ours, so there are witches, and he uses their power to countermeasure some tech problems, such as precision in steelmaking

The webnovel is called Release that Witch, and there is a lot of technical terms in this webnovel, everything is well explained and there are entire chapters about the technological development.

Sorry about my bad english/mispelling, I hope this helps.

You specifically mention cartridges

Paper cartridges have been in use for nearly as long as hand-held
firearms, with a number of sources dating their use back to the late
14th century. Historians note their use by soldiers of Christian I in
1586, while the Dresden museum has evidence dating their use to 1591,
and Capo Bianco writes in 1597 that paper cartridges had long been in
use by Neapolitan soldiers.
https://en.wikipedia.org/wiki/Paper_cartridge

No. Manufacturing precision and consistency as well as metallurgy were not up to scratch. I could also see problems with raw materials and quality control.