I read that heavy plate mail eventually gave way after the widespread use of guns, because the thickness required to stop bullets was simply too heavy for a man to wear.
This leads me to wonder about some wily blacksmiths who attempted to make bulletproof armor. Certainly better designs and materials can go a long way to making a suit of armor more effective at stopping bullets, and I can’t imagine that when guns became popular armorsmiths simply threw their hands in the air and said “I give up”. There must have been some honorable mentions, right? Maybe some examples of plate mail that COULD protect against early guns, but were prohibitively heavy. The thing is, I’ve never heard of any examples of this.
Furthermore, I’m interested to know how strong a blacksmith could make a suit of plate mail and still have it be light/flexible enough for a man to maneuver around. On the History channel there was a guy from the Royal Armoury in England who pointed out that while the armor was heavy, it was pretty well distributed over the body and demonstrated this by dancing and doing cartwheels (amusing to watch
). They also fired arrows at breastplates and showed slow-motion shots of the arrows bouncing/breaking away harmlessly without any significant damage to the armor itself.
How tough can they make this stuff? Could it be able to withstand a hail of arrows? fend off blows from countless adversaries armed with swords, axes, polearms, warhammers, etc? In its heyday (before guns) armor got pretty impressive, with full suits of plate mail. Along with a shield, a man so protected looks like he can withstand a lot of physical punishment on the battlefield.
Well first off it’s plate armor, or more accurately, articulated plate armor, not plate mail. Mail refers to chain mail armor.
Plate armor did survive to the early period of guns, though it began to cover less and less of the body as the conditions of the battlefield changed.
In fact late period armor sometimes sported a small dent where a gun had been fired at it, as proof of it’s capabilities.
Late medieval and early renaissance fully articulated plate armor was proof against most period weapons. Bows and crossbows needed to hit a less protected area (the armpits, the joints, an open visor, etc) in order to do any damage to the person wearing plate armor, in fact, most of the time volleys of arrows were expected to distract or harass heavily armored calvalry and kill or maim their horses, rather than actually kill knights.
Most melee weapons had to be redesigned to counter the quality chain mail and plate armor of the time as well. Swords became larger and were better at thrusting so as to take advantage of the added protection of armor (no shield necessary) and the power of a good thrust (in order to penetrate chain mail, or defeat lightly protected areas or articulated plate).
But your best bet against a heavily armored foe was a long and strong thrusting weapon (lance or polearm) and a stiff dagger for when/if the fight came to a grapple.
What, in the name of Garry Gygax, do you mean by plate mail? There really is no such thing outside of FRPG. Historically, there was a time when chain mail was supplemented by plates of armour but this is hardly the epitome of armour that you seem to allude to.
To summarize one of my books on armor:
It was indeed possible to make armor bulletproof, and for men to fight in it. But it was very heavy, and battlefield tactics in the 16th century began to change, emphasising speed and maneuverability, making such a heavy cavalry force obsolete. Most “cuirassers’ armor”, which was what that heavy bulletproof armor was called, was abandoned by 1650. One of the last regiments of cuirassers (English Civil War Parliamentarians) was derided as “a regiment of lobsters”. It was not a great success.
About Tudor times, there were plenty of guns on the battlefield, but people were still wearing full suits of armour.
In fact, the art of the technology of articulated plate armour reached its peek at this time. All this was done so that people could play games - jousting and the like. Some suits were very heavy indeed and totally impractical for a real battle.
Meanwhile, soldiers were wearing less and less armour. What they did wear came down to a solid breastplate and a helmet, possibly supplemented by a thick leather coat. This pattern continued for a very long time.
Contary to popular belief, the invention of the gun did not cause an overnight revolution on the battlefield. There were a few guns at the battle of Agincourt (1415) and there were still a few armoured cavaly at the battle of Waterloo (1815)!
So, can armour stop a bullet. Certainly, there was an long period where the wearing of armour on the battlefield was wothwhile. Even if the armour could not stop a bullet at short range, it could well improve your chances at long range. For a long time, heavy breastplates would be proven by having a pistol shot into it. Many such breastplates from the English Civil War period bear these marks.
Incidentally, the bullet was put into the inside of the armour as the shot would significantly deform the breastplate making it very uncomfortable to wear otherwise.
The problem was the expense, IIRC, than the weight.
Hmm, not a popular topic with the people it seems, lol… so if the backlash isn’t too serious how about I enter my small pilings of ignorance into the discussion? @ worse you’ll still get yourself a boost to the top of the board again 
I never researched the topic even when it was a big deal for me, so I have no real residual knowledge to share wit’ ya dog. But what can be said is that the weapon of choice would play a big part in the severity of the injury… at their thickest in history, I’m doubting all but the best shots could have gotten an arrow through or around a … (are we talking about knights here? ) … regardless, there were only small slits (literally) of opportunity to get an arrow in… swords would even have trouble getting through, but then you went on to axes and warhammers and I would have to stop admiring a heavy suit of armor at this point, because weapons of this type were designed not so much for penetration - armor would take the brunt of a strong blow, but the person inside would be near helpless against one that is able-bodied enough to wield one of the two-handed variety… especially the war hammer- if the soldier wasn’t knocked into the next room, I would think repeated blows would eventually use the suit of armor against it’s wearer; slowly crushing him to death . I see pole-type weapons as not so practical, but just as deadly to heavy armor- the advantge assuming the opposition had enough distance to build up speed since such weapons are of the long distance variety… a lucky shot from either the latter types of weapons would leave little rebuttal…
Now since I started this by reporting my ignorance on the topic, I’ll give you a reference for someone on here who’s got a real love for military strategy and the history of. I don’t know if his knowledge goes back as far as the age of the firearm’s first appearance- but I would think he’d have some interesting bits to fill in the empty spot you have. He goes by the SCRname: SmilingBandit…look him up, good luck with your education… it’s a worthwhile endeavor. 
Howdy Bandit LOL… looks like you showed up before I could instroduce you 
Armor of most kinds was expensive, sure, but people often claim that plate armor was the most expensive suit to have constructed.
Not really, specially not when articulated plate was becoming more prevalent. This was due to the very industrialized manner in which arms and armor were being built in the middle ages: by huge guilds in a handful of places which pumped out many pieces for various countries (one such famous place is the German city of Passau).
So the vision of armies being outfitted for war by the lone town’s blacksmith is pure fantasy.
A typical suit of plate would not cost much more (or even less) than a good suit of chain mail.