Personal body armor, plate armor anyway, had utility very much into the smoothbore era, proof against pistol at any range and most long-barrel weapons outside of what would be considered today quite short range - 50m or so. Since the fit between ball and barrel was looser - to accommodate greater rate of fire - there was a huge amount of energy loss from gases going around the ball. Also can't disregard the relatively poorer accuracy of a ball ping-ponging down the barrel before it exits.
Gunpowder weapons in the earliest of early Modern conflicts, pre-1550 or so, one gets the feeling that their dominant utility in turning a battle was "scaring the hell out of horses". Battlefield archaeology, sites from the late 100 Years War to 30 Years War, if you died from violence on the field, the most likely cause was "a horse fell on you". Also, more substantially I suspect, the morale effect. Nothing in the late medieval world was as loud as cannon. Not thunder, not anything. It's hard for us to imagine. It must have been terrifying. I suspect the closest contemporary experience is being hunted by UAS as a foot soldier.
Rifled muzzleloaders had a lot more energy, sealing the barrel. They also fixed the accuracy problem, as the projectile had to be swaged down the length of the barrel, engraving the rifling on the projectile as it went, but they had terrible rates of fire. It took work to push that lead into those little grooves.
With improved methods for loading rifle barrel weapons - like the 1772 Ferguson rifle and the Minie ball, two different solutions to the same problem - and conical projectiles like the 1836 Greener bullet, personal armor was having a more and more difficult time keeping its integrity. Furthermore, near-penetrations were just as if not more devastating than an unarmored hit, with dreadful spalling on the backside of the plate. Rifled barrels were also becoming more easily produced en masse, with the Bessemer/Siemens processes and Maudslay's lathe improvements.
Parallelling all of this, and probably of greater importance, is the growth of the conscript army post-1800. Firearms are very cheap, relative to other missile weapons. Conscripts too. Put those together and . .
By the era of smokeless powders, the jig was definitely up, apart from exceptionally specialized personal armors we saw occasionally in WW1, like the Brewster body shield or Sappenpanzer. Conscripts were too cheap, and offensive weapons too powerful. We'd have to wait for composite technology to catch up - and for the return of the full-time, non-conscript volunteer military - before we saw personal armor on the field again.
> if you died from violence on the field, the most likely cause was "a horse fell on you".
This is close to my grandfather's story. He was a Lithuanian Jew conscripted into the Czar's army and somehow wound up on a horse. They released him after he got shot in the leg, which then killed the horse, which fell on and broke the other leg. I never got more of the story than that. It may have been then that he decided that immigrating to America was a good idea.
sounds more like a freak accident if the bullet even killed the horse ... cause above theory requires gun shots having been very loud but little deadly
This (excellent) series on armor in order [1] agrees. Throughout all of history, protecting heads and torsos is the top priority for armor. Everything else follows, especially given pre-modern cost and weight restrictions.
And spears! Helmet + spear (with a shield of some sort: on the arm, in a trench, composite) is as near to the Universal Hominid Combat System as I think possible.
I think spears (I'm including rifle mounted bayonets here) have pretty much been on the outs since magazine fed firearms became a thing. Definitely since the advent of fully automatic guns.
Yes, there have been sporadic bayonet charges in recent times. But they've become extremely rare.
In contrast, helmets are as useful as ever. The ballistic protection is improving with the move from resin impregnated Kevelar to UHMWPE[1]. And they're an important mounting point for hearing protection/headphones and night vision - so much so that some people forego ballistic protection entirely in favor of lighter weight "bump" helmets.
Heck - "breastplates" have made a comeback in the form of body armor vests, being a sort of combination armor and utility pouch anchor point.
Armies with longer spears used to be the one of the deciding factors in ancient battles. Aren't rifles just a more effective way at getting the sharpy bit in to the other guy without having to heft a small tree?
I read somewhere that bayonet charges rarely came to hand to hand because either the attackers were mown down or the defenders ran away. No-one in their right mind wants to get stuck with a bayonet. Apparently the NZ Maori battalions in WWII were particularly fond of the bayonet. I can't imagine how bowel-liquifyingly scary it would be to see Maori's with 18 inch bayonets running at you.
> Yes, there have been sporadic bayonet charges in recent times. But they've become extremely rare.
Bayonet charges yes, but a bayonet (or in modern times, more like fastening a knife to the assault rifle) can be nice to have as a sort of last-ditch thing in a close-quarters situation.
I don't think that's the case. Maneuverability matters in close quarters, and a spear doesn't work if the adversary is too close. If the adversary is far enough for a rifle-length spear to work, shooting them with the rifle also works. Closer than that and you're better off with the knife or your bare hands.
(Also, you might be better off using the rifle as a club.)
> a bayonet (or in modern times, more like fastening a knife to the assault rifle)
I mean... that is what a bayonet is. There's a reason why military rifles still come with bayonet lugs on them.
> a bayonet ... can be nice to have as a sort of last-ditch thing in a close-quarters situation.
There are a lot of downsides to a bayonet.
1. It's a sharp knife sticking out the end of your rifle. So if you have to transition to a shotgun or sidearm and it flops down to your side because it's on a sling, it could cut you. It can also cut a teammate on accident depending on what you're doing.
2. It increases the length of your rifle by 4-6 inches. Which is huge when it comes to room clearing. There's a reason why 10"-12" barrel rifles are so popular in that role - it's way easier to maneuver through doorways and around obstacles. It's also weight added to the end of the rifle. Not a huge amount, but 2/3 of a pound can still be a problem. Especially if you're fighting off and on for hours.
3. It takes up space and weight allowance on your belt or vest. It could have been 1-2 extra mags. Most people just wouldn't consider it a good tradeoff.
> There's a reason why military rifles still come with bayonet lugs on them.
At least in the US military, I'm fairly certain the reason is entirely historical anachronism due to the the incredible longevity of the M-16/M-4 family of rifles. Bayonet training was removed from Army basic training well over a decade ago and a quick glance at the current M-4 replacement program suggests that the bayonet lug has been removed from the requirements for a new Army assault rifle.
No, a bayonet as back up weapon hasn't been effective in a long, long time. We've seen it as a desperation weapon, during Stalingrad and other battles where both sides logistics were stretched beyond - far, far beyond - their breaking point. Fuel, shells, tanks, bullets, then shovels, axes, knives and teeth . . all were weapons of war in the great inferno of the early 20th century . . but no one, ever, would substitute a bayonet for a spare mag on an autofire weapon. Even basement clearing.
I can see, in some circumstances, a case for knives as close-in weapons during reconnaissance or other stealth missions, but even in those circumstances, an army with functional supply systems will pack a DeLisle Carbine, a "hush puppy", a Welrod pistol, or one of the many often homebrewed stealth weapons enterprising recon squads often baked up.
I agree. One thing that many people don't really comprehend was how little combat occurred with swords vs how much occurred with spears and ranged weapons.
The typical view of a samurai or a knight in heavy armor swinging a sword around is a view of that soldier at likely their last moments. They most likely had started with weapons that provided greater standoff from their opponents and only when those weapons were irretrievably lost would they have drawn their sword. Weapons form part of systems, and for thousands upon thousands of years, a pointy bit at the end of a long stick dominated most systems across the planet.
The Ancient Chinese called the spear the "King of Weapons" and over the centuries developed a very large number of variants and included shield and armor.
The Europeans likewise underwent a period of rapid polearm evolution from the Renaissance to almost WW1.
Shaka Zulu, one of the great military minds of Africa became famous in part for reworking the traditional spears of the Zulu into hybrid spear/swords backed by shields in tight formations.
Prior to this the Phalanx was a spear-first strategy, and the Roman Infantry worked with more flexible spear and shield configurations -- the gladius was not a deciding weapon and may have been kept so short in order to support close-in work behind the shield wall of a Roman formation.
So dominate was the methods for employing spears in combat that armies that went all-in on firearms still marched in the same type of formations as they had with spears well into the 19th century. The World Wars finally broke that habit.
Can't put a premium on head protection. It's not just brain injury - it's where all your sense organs are, as well. Stuff flying into your eyes and ears will make you combat ineffective even if you're not concussed. It tends to be the first thing to get hit when something falls (or is dropped!) on you, not an uncommon thing to have happen in premodern war. Or even in modern war. Furthermore, it's where most of your environmental heat loss occurs, so you'll want something on your dome no matter what. Might as well add some leather/horn/wood/metal.
Head protection probably naturally flowed from protective headgear worn against the environment, which can be seen in decorative ceramics as far back as 25,000 BC. It might very well cross Hominid species boundaries, as the spread and success of H. Erectus was based at least partly on fire usage. Today, many species of Pongines use large leaves and other material as semi-wearable rain shelters; it's a habit the locals have picked up, as well. Soft armor, who knows? Textiles don't age well, unfortunately.
The first signs of military helmets (and shields!) very nearly precede the earliest dates for domestic agriculture, lending weight to the growing view that coercion led to centralized agricultural statism, rather than the reverse, which is the more standard, traditional view. The "Meskalamdug Helmet" is a a highly-ornamented example of an early helm, stylized in such a way that suggests the form of the infantry helm was a recognizable semiotic to contemporaries. You don't build a statue of a cell phone in 1880s London, so they made it look that way for a reason.
And again we come to morale. A helmet de-humanizes the soldier, both to the enemy and to allies, which keeps combatants from engaging in normal nonverbal communication. Restrict empathy, and you increase the chance of violence and the strength of the violence when it does happen. So you wear a mask when you do it, a scary one, like a lion head or an angry fire being. It's pretty common-sense stuff - I mean, look at the plumes on the Spartan's helm - but it's cross-cultural as well, which hints at a deeper principle. Helmets from the Neolithic far east seem to have developed this aspect first, as they start out from ceremonial pottery, then the same design reinforced with basketry, and then you have the same design as a lacquer mask on a more dedicated military helmet. We do have to be very careful here, because the pattern of civilization building is just very, very different in China, and probably all over. It's deceptive, you're tempted to think of it the same, but look at the details of the timeline and you realize whoa, hold up a second, they did this waaaayyyy before this other thing.
The article implies the use of armor dropped because it became more expensive to create armor that could resist firearms and armies grew too big to be fully equipped with it. But he shows that some soldiers could still afford it and that smaller armies with armor could defeat much larger ones with out it.
He lists several instances where a force of armored heavy cavalry defeated armies several times its size. He also shows that it would take about a month of average soldier pay to afford a cuirass or 1.5x years of average soldier pay to afford full plate armor. If an army in full plate can defeat a force > 2x its size, it would seem economically viable to cut it in half and armor it.
So then, why did the size of armies grow? If a smaller armored force could route a much larger unarmored force in spite of firearms... why didn't more armies stay smaller and armored? Armor is an occasional expense -- purchased once, repaired infrequently. Soldiers are a constant expense -- they have to be paid, fed, housed, etc.
If firearms were ineffective against proper armor, why did their use spread? I've always understood that the advent of firearms and their effectiveness led directly to knight's loss of dominance on the battlefield but this article strongly implies otherwise. So if it wasn't the firearms, what was it?
I'm sure there are answers and a ton of nuance, but this article didn't communicate them clearly. It provided a bunch of counter-examples to undercut the previous understanding and then vaguely hand waved at a new understanding with out fleshing it out convincingly.
"If an army in full plate can defeat a force > 2x its size, it would seem economically viable to cut it in half and armor it."
You cannot really generalize those things.
It depends on the battle site. Heavy cavalry cannot operate everywhere. Not in a city, not in dense forest, nor mountains. And not in heat. In general, armor limits mobility.
Also the heavy cavalry is an elite formation, taking years to train the knights and (breed) the special horses. Hard to scale.
A simple human infanteryman on the other hand: give him a cheap mass produced rifle, drill him some days and then put him into a formation. That scales easily. Then you can also give him a long lance and drill him some days more and any cavalry charging at a prepared position will be a bloodbath for the horses. And once down, the shiny knight could barely move and was an easy target.
But yes, at the right moment, a heavy cavalry charge at cheap musketeers was indeed shocking and routing formations en masse. It takes great discipline holding a line, when thousands amored battle horses charge at you.
I think it is hard to generalize off of a couple examples like this. It is an iterated game with multiple strengths and weaknesses and also scaling issues.
For example, if heavy cavalry can still beat an all-firearms army, the obvious thing to do is mix in some pikes. Pike and shot had a whole era, haha.
There is a game on Steam called 'Pike and shot' by Slitherin. it is quite reminiscent of a tabletop game. Worth a look if you are interested in the era.
I’ve been interested vaguely in these sort of computer war games (seen too many complaints about the unrealism of total war lately). But co-op against AI’s seem to be very rare in the genre, which is essentially table stakes for me.
I've got some interest in Japanese military history and can say the story there was basically the same as in Europe with a long coexistence between firearms and edged weapons that mostly comes to an end when guns got a lot more lethal in the 1800s, like
Curious fact about Japan, it was united under, if memory serves well, Ibunaga using the, by some accoints, best firearms rquipped army equiped with the best muskets of the time. Only to have forearms basically outlawed once Japan was united under a new Shogun.
Edit: Good article so, goes over all the important aspects, including logistics (bonus points for that!), and shows that forearms didn render armor or cavalery obsolete over night.
If you’re on a relatively remote and isolated island, once you’ve seized control, ensuring you have no real challengers by outlawing weapons is pretty doable.
If you’ve got long, porous borders and are in the middle of the route everyone uses to pillage it isn’t.
In the Tokugawa period warriors were honored in the abstract but there was very little war. Police were expected to disarm misbehaving, drunk, etc. samurai with a hook
Now I can imagine catching a sword with one of those (have a bit of experience with Okinawan weapons and such) but I would not want to do it against anybody who was actually good with a sword (so much in Martial Arts is about knowing what to do ahead of time and doing it with conviction). At the beginning of the Edo period you had some great warriors such as
The fact that a peasant with a musket and 1 weeks training could kill an elite Samurai who had trained all his life, threatened to upset the whole order of society. Hence the outlawing of muskets at the first practical opportunity.
> Armor is an occasional expense ... Soldiers are a constant expense
I'm not an expert, but it's worth considering that you can't ramp the production of armor in the same way you can ramp conscription. So to have enough armor, you'd need to be buying armor for nobody in times of peace, which is a tough decision, especially if you're living in an era where firearms are improving rapidly.
And unlike armor, a musket is not made to fit. Even if you tried, you wouldn't have been able to stockpile quality armor for a time of need, outside a privileged warrior class (who did wear armor to battle)
This period actually saw the rise of "munition armor" which was meant to be mass produced. This was part of the reason for the transition to 3/4 cuirasses - the arms and legs, in addition to being less vital, are also where a lot of the customization was needed; if you stop armoring them then everything becomes lighter and cheaper.
Also, armor sucks to actually wear. It restricts mobility, wears everyone out faster due to weight, causes issues with heat management in hot climates, etc.
Unless there are pretty good odds the risk of getting shot is worth the payoff (and the real costs are therefore worth paying), it’s way easier to just not use it.
Ain’t nobody running an obstacle course in good time in Level 4 armor (or plate).
The plate armour guy was marginally faster than the guy in modern soldier's gear. Plate armour was less cumbersome than most people imagine and the weight is more evenly distributed than a modern soldier (where it is nearly all on their back).
Sure, but most people imagine plate armor means you can’t get yourself up off the ground and you’re stuck and dead if you fall.
And those folks actively trained with that armor on. A noob would have a MUCH worse time.
They also would have been a LOT faster without any armor at all on (once they adjusted for the lack of weight/restriction). Also, probably dead if they got hit with whatever the armor would protect them from.
I know, I’ve had to do courses like that with and without body armor, and wore Level IIIA body armor for years. You get used to it, but it is ‘friction’ that you’d be faster without.
>Sure, but most people imagine plate armor means you can’t get yourself up off the ground and you’re stuck and dead if you fall.
I think that migth be another one of those myths we can blame the Victorians for. Also the black and white film of Henry V (?) where knights are shown being winched on to their horses. They weren't going to wear armour so heavy they couldn't get up in - they weren't stupid!
>A noob would have a MUCH worse time.
Indeed. People wearing plate were professional warriors, trained from childhood.
> So then, why did the size of armies grow? If a smaller armored force could route a much larger unarmored force in spite of firearms... why didn't more armies stay smaller and armored?
Because of societal changes, as governments became more centralised and central authorities (usually monarchs) didn't want to rely on aristocracy, who could easily challenge their power, but preferred the masses, who were easier to control as bureaucratic and propaganda apparatus of the state grew more organised and powerful.
An interesting point, I remember hearing of the janissaries, who were slaves, but well trained and equipped; there appear to be instances of those janissaries seizing political power. Relying on a military to maintain power is like a mouse keeping wolves chained up, and using the wolves to control lions. Its far more reliable and economically feasible to control the minds of the populace, as long as you have control over what they see/hear.
Oh, the Osman Empire had a completely different societal structures which changed greatly over time, including the roles of janissaries. But the function of the janissaries was similar: not part of the nobility, completely uprooted from their family and social circle, they owed all they had to the Sultan, so they helped him safeguard his power from entrenched power sources — at least that's how it worked during some periods.
My original comment was more about feudal Europe in territories of modern France, UK, Germany and to some extent Italy and Spain. Even in medieval Moscovy and Poland things were not quite similar.
Losing power isn't really an issue as long as those who had it don't lose status. The defining property of situations like the Janissary one is that the group coming into power is exempt from status.
Armor is a one time expense, that's the thing. But more men is a no time expense unless you are at war. This is before the establishment of (modern) standing armies, and the occasional armored units victorious over larger unarmored ones were the closest thing to an exception.
The initial decline of the knight was perhaps less about firearms than about pikeman tactics (tercio and all that) with the various revivals of heavy cavalry mentioned, e.g. under Gustavus Adolphus, being merely reactions to shifts in the balance between pike and shot. When it's pike and shot vs pike and shot they will eventually try to outbid each other in focus on shot, until they become vulnerable again to the heavy cavalry charge that had been deemed obsoleted by pike.
Much of the time the size of your army was determined by the number of able bodied men that lived on your lands, and they were armed with whatever weapons and gear they brought with them. Feeding and housing them wasn't that much of an expense, either, since armies would often confiscate whatever food they needed from farms and towns along the way (leading to the 3rd amendment of the US Bill of Rights.)
It wasn't until standing armies with standardized weapons and gear became more of the norm that a smaller, better equipped army was really even an option, and by that point firearms technology (and artillery) had progressed enough that armor wasn't very useful. Even then, soldiers wearing a cuirass into battle were still a thing up until WWI, so it's not like the practice died overnight.
> Is it an axiom of civilization that destruction always costs less than construction?
Defense and Offense vary in power over time.
In the middle ages, it was possible to construct a suit of armor that effectively made you invulnerable. A small force of armored men-at-arms could defeat a much larger force of peasants because the peasants just wouldn't be able to injure them effectively.
Additionally, castles and other fortifications increased the power of defense.
Firearms swung the advantage to the attackers - giving conscripts a way to pierce plate mail, and cannoneers a way to take down castle walls.
Barbed wire and machine guns swung the balance of power back towards the defenders. Largely static trench warfare was the result; even with overwhelming artillery fire, it was extremely difficult for determined attackers to mount an effective assault.
Stormtrooper tactics, tanks, and airplanes all boosted the power of offense making deep penetrations into enemy lines a routine occurrence in WWII.
Nuclear weapons were initially a massive boost to offense when only the US had them. But with the advent of MAD they are firmly a tool of defense[1].
Even with modern weapons at their disposal, economic conditions can also affect the battlefield - the Ukraine war is very much a defense-centric war. This is partially because of the potency of SAMs and partly because Ukraine is starved of artillery munitions. Among many other reasons.
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1. At least until they're next used in anger. No one really knows how MAD will actually play out. Hopefully no one has to find out.
Isn't the goal of the "smart bombs" rather to avoid having to blow up hundreds of structures that cost thousands to get at the one (and to get that one really, properly blown up)?
In a weird sense smart bombs might be considered construction, in much the same way as a carefully-controlled chisel creates a statue rather than destroying a rock.
I'm not making a moral equivalence here -- please don't construe my comment to mean that blowing people up is somehow good. But from the perspective of the person dropping the bomb, they are reshaping rather than destroying. If their goal were purely destructive, there are cheaper means available.
> Armor is an occasional expense -- purchased once, repaired infrequently. Soldiers are a constant expense -- they have to be paid, fed, housed, etc.
At the end of the article the author notes that armor would actually have to be repaired quite often, and that doing this for large armies was likely impractical. Further, while a small armored force might be able to defeat a larger force in a single battle, there are definitely advantages to having more warm bodies: you can cover wider areas without gaps, you have more manpower to build fortifications, you can rotate people through stressful parts of soldiering, etc. It doesn't necessarily follow that the massive upfront cost is justified, especially if you can get a lot of the benefit by only having a much smaller number of elite units equipped with such armor.
Then there are further logistical concerns - soldiers don't just need to survive battles, they need to complete objectives, which means a lot of marching to locations and moving around to deal with situations. While craftsmen of the period were capable of producing bulletproof armor, it was nevertheless getting heavier - not so heavy that you couldn't move around in it, but heavy enough that you might move slower. As per the article, the trend was toward lighter, more maneuverable units armed with a lot of firepower. While heavier units could still win from time to time, that doesn't necessarily mean they were better.
> So then, why did the size of armies grow?
> If firearms were ineffective against proper armor, why did their use spread? I've always understood that the advent of firearms and their effectiveness led directly to knight's loss of dominance on the battlefield but this article strongly implies otherwise. So if it wasn't the firearms, what was it?
Armies weren't growing because of the adoption of firearms, firearms were being adopted because armies were growing. Firearms were relatively cheap (especially compared to the armor required to protect against them), and compared to weapons of similar range and capability they required little training. And if you look at the evolution, it's basically you start with an army of pikemen, then you have an army of pikemen where they strap a gun barrel to their pike to get one shot off at the start of the engagement, then you have pikemen where the pike is a musket and they plug it with a bayonet, and eventually you have socket bayonets that allow the soldier to have a perfectly functional musket and pike at the same time; and at that point we start calling them musket men instead of pike men. Firearms were adopted because they were a cheap and seamless way to boost the effectiveness of a fighting force, not because they were a counter to any particular force on the battlefield.
At this point in time political organization had increased to the point where wars were being fought between nation states, and there simply weren't enough people who had been training for their whole lives to be longbowmen or lancers to fill the ranks. Really this a return to form, in more politically organized areas and time periods, such as China or the Roman empire, armies in the hundreds of thousands were not uncommon. Medieval Europe just had a long period where no one could consistently muster a force that could resist a good sized group of knights on horseback. Heavy cavalry were still effective, as demonstrated by the Winged Hussars, but you needed them to scale to appropriate numbers and use them appropriately in the new warfare framework.
Cool looking game. Added to my Steam wish list. I'm curious about the scale of the game. Aside from the unique concept, the combat reminds me of Mount and Blade quite a bit, but the scale looks larger. How many individuals are there on the battlefield? Was the tech to support such a large scale battles a challenge?
Yes, it was very challenging. It is in the thousands. In the trailer that is in the neighborhood of 4-5k soldiers. We are still deciding how many will go in the final game. But the number would only go up from the trailer(The trailer is essentially a playable build).
I'm pretty sure that is more than bannerlord, which I think is around 1000, but maybe they have less on consoles.
Thanks! Really looking forward to it. I play Bannerlord on PC with settings pretty much maxed and my recollection is that 1000 is about right. A 4x (or more) improvement over that is seriously impressive.
For LOTR fans, the hussar charge at the Siege of Vienna was the inspiration for Tolkien’s epic cavalry charge of the Rohirrim that lifted the Siege of Minas Tirith.
If you are interested in armour I strongly recommend a trip to either Leed Armoury (Leeds, UK) or The Wallace Collection (London, UK). Both have amazing collections of medieval and other armour. Some of them are incredible pieces of craftsmanship. IIRC NASA studied Henry VIIIs armour when designing early spacesuits.
Youtube video's by Todd's workshop show that good quality plate was very effective at stopping arrows. Even heavy welsh/english warbows at short range. But a high volume of arrows would potentially find gaps in the armour.
Gunpowder weapons in the earliest of early Modern conflicts, pre-1550 or so, one gets the feeling that their dominant utility in turning a battle was "scaring the hell out of horses". Battlefield archaeology, sites from the late 100 Years War to 30 Years War, if you died from violence on the field, the most likely cause was "a horse fell on you". Also, more substantially I suspect, the morale effect. Nothing in the late medieval world was as loud as cannon. Not thunder, not anything. It's hard for us to imagine. It must have been terrifying. I suspect the closest contemporary experience is being hunted by UAS as a foot soldier.
Rifled muzzleloaders had a lot more energy, sealing the barrel. They also fixed the accuracy problem, as the projectile had to be swaged down the length of the barrel, engraving the rifling on the projectile as it went, but they had terrible rates of fire. It took work to push that lead into those little grooves.
With improved methods for loading rifle barrel weapons - like the 1772 Ferguson rifle and the Minie ball, two different solutions to the same problem - and conical projectiles like the 1836 Greener bullet, personal armor was having a more and more difficult time keeping its integrity. Furthermore, near-penetrations were just as if not more devastating than an unarmored hit, with dreadful spalling on the backside of the plate. Rifled barrels were also becoming more easily produced en masse, with the Bessemer/Siemens processes and Maudslay's lathe improvements.
Parallelling all of this, and probably of greater importance, is the growth of the conscript army post-1800. Firearms are very cheap, relative to other missile weapons. Conscripts too. Put those together and . .
By the era of smokeless powders, the jig was definitely up, apart from exceptionally specialized personal armors we saw occasionally in WW1, like the Brewster body shield or Sappenpanzer. Conscripts were too cheap, and offensive weapons too powerful. We'd have to wait for composite technology to catch up - and for the return of the full-time, non-conscript volunteer military - before we saw personal armor on the field again.