Oh, feel free to hijack. That’s another question I had floating in my head that I’d love the answer to also. 
It was down, but its back, baby! 
From what I’ve heard, Kevlar is pretty damned hard to tear, making it very useful against knives and arrows, but I don’t currently have a cite. I doubt that an arrow would go through a Kevlar vest with ceramic plates.
Best protection by far is to be standing behind the opponent when the shooting starts.
YMMV
I have made butted mail using 5/16" spring steel lock washers; a machinist who sold me the rings tested a sample on a press and said that based just on the strength of the material, it was probably bullet proof. However, although the bullet wouldn’t have penetrated the mail, the force of the blow would have driven the mail an inch or two into the body, which would still sting like the dickens and, depending on where you got hit, still prove fatal.
Oh, another SCA guy here. forgot to mention that.
Tests with chainmail hung over a pig carcass and struck with a sword showed that, again, the mail held, but would get driven into the target by the force of the blow. Riveted mail fared better than butted mail. For more information on this, you can search around at The Armour Archive; like planes on treadmills, this has been discussed there in great detail.
I also have a picture of an SCA armourer who made a full Maximilian breast plate, took it into his back yard, put it up on a post, and fired a black powder revolver at it from 10 feet away.
There’s a hole through it, just above and to the right of his belly button. He left it there as an object lesson in why they stopped wearing the stuff.
Ancedotal story: A man who was at my grandfathers house many years ago had been a medic in Vietnam. He told a tale (unsubstantiated, but it was a cool story) about a (squad? platoon?) he was with who got in a firefight with some VC.
When the shooting stopped and the VC were all dead of fled, they swept the trees and such for bodies, and found a few. One of them appeared to have been a leader of some sort, and also appeared to have been wearing a maile shirt.
The rounds that struck him also pulled lengths of maile through the wounds, which were through and through, effectively stitching the VC.
As I’ve said, no proof, but it made for an interesting tale.
Also, former SCA guy here, and there is no way a heavy shirt would stop a modern bullet. Numerous layers might (big might!) manage to stop a large ball from an Arquebus or large bore match/flint lock, but that’s a Might Big If and the target would pretty much be immobile from the weight, imo.
Kevlar will stop a slashing knife attack, but isn’t likely to stop a stabbing attack, ceramic plates, if they’re in the right place at the right time will.
If you look at the “Box O’ Truth” site I linked to, particularly the shotgun damage, you can see how fibrous the Kevlar is.
An icepick or even worse a bodkin head arrow would most likely not be stopped.
kidchameleon’s right it is hard to tear or cut, but unless the Kevlar is laminated to a substrate the fibers will spread apart.
Kevlar would probably make for a good gambeson (a padded jacket, worn under most armor types) Ludovic.
One important thing to remember about plate, usually it gets heat treated!
First an annealing to relieve stresses in the metal from shaping (the shaping itself will work-harden the metal too), then an actual heat treat to harden and temper.
Thanks Ethilrist, great site!
CMC
Apparently DuPont’s new Kevlar is treated as crowmanyclouds meantions to make it a better defense against stabbing weapons.
Warning, that’s a PDF.
So is anyone willing to provide me with some samples of their armor to test at the range?
It was my understanding that chain mail was worn over some sort of padded jacket or a heavy ox leather undergarment just because of this problem. The mail would turn a sharp blade but would not protect from blunt trauma. The padding under the mail shirt served to soften the blow.
As far as plate armor went, in its last days of general use during the time of the English Civil War and the Thirty Years War, the stuff was “proofed by taking a shot at it from pretty close range with a big old .75 cal horse pistol. If the ball went through and bounced around inside the item was rejected. It the plate merely dented it was safe to use.
Remember that until the development of military rifles in the late 18th Century an armored soldier wasn’t going to run into anything more potent than a musket or pistol ball which probably didn’t have a muzzle velocity of much more than 800 ft/sec and was not effective at more than 100 yard range. A German Jagger rifle, or a British Baker Rifle or a Pennsylvania or Kentucky rifle had a significantly higher muzzle velocity, maybe as much as 1500 ft/sec, and was effective out to close to 300 yards. That isn’t much compared to the 2300 ft/sec produced by a 30/06 cartridge but it is a considerably bigger thump than the impact of a smooth bore musket or pistol.
You might as well ask someone who builds boats in a bottle to give you one to shoot to bits.
Also worth pointing out that a Pennsylvania Rifle (don’t know about a Baker or a Jagger) fired a projectile that was of a narrower calibre than the Brown Bess musket, so not only did it have a higher velocity, but it was gonna put it’s force into a smaller surface area when it hit you, thus giving it even more penetrating power against armor.
It’s also worth mentioning that Kevlar is basically modern-day chainmail. Only instead of linking iron rings together, we have a multi-layered synthetic weave which works in basically the same way. Also, some modern tanks drape chains around their vulnerable areas to combat against shaped-charge anti-tank weapons which are designed to hit the armor and then discharge a highly focused blast. This way the anti-tank round hits the chain, detonates, and the shaped charge is “out of focus” and thus doesn’t apply it’s payload effectively against the tank’s armor. Thus, everything that is old is new again.
He’s generally right. Good Chain, with a good set of padding or tough leather under it, will stop low penetration stuff. Maybe buckshot at some longish range, maybe those special low penetration rounds they issue to Skymarshals & such. But large caliber but low velocity has less penetraion than small caliber. Thus, a .223 is much better at going through armor than a .45.
A real solid breastplate will stop rounds- they had some in WWI and even WWI that would- but they weighed to much to move in. In WWI, they were used for snipers & machine-gunners, in WWII they were used for wing gunners on B-17’s.
However, all the above could stop shrapnel- or make it worse, I guess.
Today, in modern combat- if you had some titanium mail- or welded stainless of fine links- I’d wear it over nothing (there’s other stuff other than high powered rifle bullets out there, you know). In fact, titanium could be fairly effective.
Good brigantine could be effective- if the plates were thick enough*- and so could a breastplate of modern alloys.
- in fact, some flack jackets are basicly brigantine.
Oh, good point. I found a website for a guy that made a full suit of mail (coif, hauberk down to the wrists & knees, mail pants. The full suit weighed 120 pounds.
He decided not to try and fight in it.
arg. I meant, he made a full suit from the same type of washers I used. People who make mail to fight in in the SCA use larger rings, so a shirt only weighs 20-30 pounds. Some people wear rivetted titanium (mostly just for show), and those weigh 5-10 pounds.
Well, if they’ve got one to spare…
Hmm, I’d love to get a set of riveted Titanium. Any websites for this? eBay?
Once upon a time “chainmail” was 
In Soviet Russia, mail chains you.
In trying to find some links to modern mail based body armor, I found this, CAPS body armor by the company that made the airbags for Mars: Pathfinder, Spirit & Opportunity.
You too, eh? I post on five or six message boards, and I utterly despise that smiley in all its various incarnations. I believe there is no need for an “I’m a smug, holier-than-thou git” smiley.