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Bullets vs Breastplate

SeverinR

Vala
Grenades versus knights made me wonder about firearms.

Firearms made armor obsolete.
What modern firearms would penetrate a bronze breast plate or other newer metal plates?

I figure most rifles would, thinking even a .22 mag could. (Rifle not pistol, not enough speed in the short barrel is what I'm thinking)
What pistol? (3-20 yrds range, ie shooting knight before he could reach you with his sword.)
I believe:
44mag and .357 would.
Thinking .22-.32 wouldn't, not enough mass and speed.

10mm-.40 and .45 would.

9mm heavier rounds might, its a high speed round, so possible to glance off.

.38 at the right range with the right bullet.

Thinking ball ammo would be more likely to penetrate, expanding bullets less likely.
Defense rounds- hydro shok, glaser would be very unlikely.

Thoughts?
(I admit this is not research on anything I am working on. Just wondering.)
 

T.Allen.Smith

Staff
Moderator
I've never shot a breastplate of course, but I have shot car doors. Nothing criminal mind you, just a strange shooting range.

From what I witnessed, even a 22LR round will penetrate the metal door, however it will not fully penetrate the door interior. Faster rounds, of smaller caliber (like the 17HMR) will penetrate due to the increase in velocity. Larger, more powerful pistol rounds certainly can. I've never fired a 25 or 32ACP in this capacity though. You are correct that ball ammo (full copper jacket over the lead) will penetrate farther than hollow points which are designed for maximum expansion.

A high powered rifle round (longer casings with more powder like the 223, 308, 30-06) will penetrate steel plate. To shoot steel targets with a rifle you need to use hardened steel at distance, and the plates are thick. It would not be possible to wear that sort of plating as armor.

Pistol rounds generally can be fired on metal targets that are not made of hardened steel, though these would still be too thick and heavy for armor. Keep in mind though, these targets are swing plates. That means the target is swinging with the force of the bullet. An unmoving steel plate would likely dent or even allow bullets to penetrate to greater degree, even pistol rounds.

I wouldn't trust a breastplate of standard thickness to stop any bullet, certainly not a rifle round or any commonly used defensive pistol round (380ACP & up). The best case scenario would involve a small caliber bullet impacting a rounded curve of the armor and deflecting.
 

Surad

Minstrel
All of those rounds would be able to defeat a medieval suit of armor. Even the best plate armor won't stand up to them. You have to remember that the early bullets were not very aerodynamic and were 100% solid lead. Modern ammunition is much, much faster and they're jacketed to boot, which gives them far more penetrative power than any old musket round could dream of having. Even a .22 LR would probably punch through a breastplate, which means round like the .380 ACP or 9mm parabellum would go through, even if they're hollowpoint bullets.
 

FarmerBrown

Troubadour
I could've sworn this was a Mythbusters episode but maybe only in my dreams :-( I can't find evidence of it anywhere! Fascinating though.
 
They Mythbusters episode you might be thinking of is the one in which they test the ability of James Bond to blow up a propane tank with a handgun. They can't. They find another way, though. Here's the conclusion.
 

SeverinR

Vala
I knew period metal was softer then hardened steel, but I think it is harder then most people think. commonly breast plates would be2-3mm or 10-14 gauge. Ok, Not a lot of metal there.

I shot a thick metal plate once. It dented the plate. We stopped shooting when we hit the plate center and the bullet bounced back towards us. Would recommendlong distance if you want to shoot hard metal.

I found someone that says an old 3/4 ton pick up fender was 16 gauge, possibly14. (old cars used better metal then cars today, by intention, cars today are meant to absorb the impact not with stand impact, which transfers the energy tothe occupants.) Washer machines are 26-28 gauge.

I saw a propane tank hit by a bullet, one just poked a hole in it, the otherignited the escaping gas and it was like a blow torch and the tank spun as itsprayed, but not an explosion. As they say on myth busters, don't try this at home.

Back to the future III, Marty used a cast iron stove door to protect him from a bullet. Pretty thick, but not sure a .45 wouldn't penetrate. (distance lessthen 10 yards)

OK, I based my original thoughts on bullets versus flesh and then tried to adjust for having metal in between the gun and the flesh. .22 doesn't penetrate to well, so thought it would no do well with metal in the way.
16 gauage isn't very thick, so now I might believe the bullets might penetrate.A tin can might equal 16 gauge with the two sides, but armor wasn't made of tin. (also again, most cans aren't made of tin anymore.)
3mm of non-hardened metal will be penetrated by most modern firearms, still thinking less then .38(.380) would be questionable. But they are questionably efficent in unarmored people.
 
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Hi,

Mythbusters have done any number of epps on this, including weather paper armour can stop a bullet. It can by the way. It really all comes down to the basic properties of the armour and the bullet. Medieval armour would not stop a modern bullet or a musket ball. That's why rifles killed armour. But better metal purpose worked to stop penetration might. Even at 2 to 3 mm thick. And as for bronze armour, it may be old but there are many alloys of bronze that are far stronger than the old stuff.

Pick your bullet and your armour and then do a little research.

Cheers, Greg.
 

Malik

Auror
If steel would stop a bullet, we'd be wearing steel armor. We don't. I believe that most medieval armor wasn't steel, anyway, but that's another argument altogether.

I've seen metal-jacketed rounds go through both sides of a car -- civilian vehicles do not qualify as hard cover no matter what Hollywood says -- and the armor we have to wear to stop even a relatively low-power round (7.62X39mm, which is roughly the ballistics of the old lever-action 30/30) is inch-thick, super-heavy ceramic encased in epoxied Kevlar and sometimes backed with titanium. The titanium is there because when those plates take a round, the ceramic shatters. This stops the bullet by robbing it of its momentum, but it tends to leave you curled up in a ball, making little creaking noises and seeing electric-blue spaghetti every time you blink. Bullets are really powerful.

I would not believe that any European medieval armor would reliably stop a bullet. I don't think any modern steel will. If it would, we'd use it instead. At least, I hope we would. Ceramic armor blows.
 

T.Allen.Smith

Staff
Moderator
I've seen metal-jacketed rounds go through both sides of a car -- civilian vehicles do not qualify as hard cover no matter what Hollywood says

Truth, a lot of Hollywood cover is complete bunk.... And once you step into battle rifle rounds, like the 308 (7.62x51), the bullet will punch through a cinder block wall. You don't need the big 50 cal rifles to get baddies on the other side.
 
Re paper stopping a bullet, a Nick Carter espionage novel I read when I was a kid noted that a folded over Sunday NY Times would stop a .22 bullet. I've always wanted to test that.
 

T.Allen.Smith

Staff
Moderator
Re paper stopping a bullet, a Nick Carter espionage novel I read when I was a kid noted that a folded over Sunday NY Times would stop a .22 bullet. I've always wanted to test that.
A couple stacked phone books might, but I wouldn't trust a folded newspaper over my heart. As stated above, I've witnessed 22LR penetrate the outer metal of a car door.

Nick Carter is full of it....
 

locofife

Acolyte
I wouldn't expect medieval armor to stop any modern bullets unless the angle happened to be just perfect. A .22 bullet can travel a good mile before running out of steam.
 
A .22 pistol, it might not... well, not quite as impossible. Caliber's only a bullet's width, not its length or the gun's efficiency.
 
Hi,

Don't know how thick the newspaper mentioned is, but it might work. I just found the mythbusters epp summary from the wiki for the paper armour vs steel armour vs bullets etc:

"Kari spoke with antique armor expert Greg Martin, who explained that paper armor was in use as early as 600 BC and was built up from layers that may have been impregnated with resin or shellac. The Build Team tested several formulations for penetration resistance and found that a thick layer of folded paper, with no resin, gave the best results.
Using an armor sample (1⁄2 in (13 mm) paper vs. 1⁄32 in (1 mm) steel) placed over a block of clay, they tested resistance to blunt force, swords, and arrows. The paper did as well as steel in the sword and arrow tests, failing only the blunt-force test, so the team built a full suit of paper armor to match against a period-accurate steel counterpart.

Each team member ran one of three timed courses in both armor types to evaluate speed, endurance, and agility; paper outperformed steel in all three. Finally, they attacked the suits with arrows, swords, and two different firearms - an 18th-century flintlock pistol and a 19th-century .45 revolver. Both armor types resisted every attack except the .45, leading the team to classify the myth as plausible. They pointed out, though, that the paper armor could quickly begin to disintegrate if it got wet or took repeated blows (both of which happened during the full-scale tests)."

Cheers, Greg.
 

Tom

Istar
Yeah, that's a .22 for you. The only thing I use mine for is plinking and squirrel hunting. No real criminal would use a .22. Their penetration and power aren't the best--a human being can absorb several hits from a .22 and keep going, as long as no vital areas were hit. On the other hand, one shot from a .30-06 and you're down.

I really wouldn't put my faith in the gun if the caliber is on the lower side. Plate armor was effective at preventing penetration. It may look thin, but it can take a hit.
 

Sheilawisz

Queen of Titania
Moderator
I have no experience with firearms, but I shoot everyday with my air rifles and I frequently watch videos online about shooting tests, damage examples and reviews in general.

Something that surprises me a lot is how many people think that the lowest caliber bullets are weak and do not offer a serious threat. I believe that a bullet is a bullet, even if it's small, no caliber is to be underestimated. I know that the .22LR can reach very high speeds and attain a deadly penetration power, and there are many examples of this caliber being used in criminal activity.

My air rifle can pierce steel cans easily, the pellets create a sharp-edged exit hole and sometimes the can barely moves at all. The same projectiles can punch half-an-inch deep holes in hardwood, not to mention that they dent the brick wall in my backyard. I have read many stories about people severely injured and even killed by this kind of weapons.

Even the smallest bullets are far more powerful than air rifle pellets, so yes, the .22 caliber must be taken seriously.

Medieval armor would not stop bullets directly, but perhaps it could deflect them depending on the angle. Even in that case, enough energy could be transmitted to the person wearing it and the impact would cause serious damage anyway.

I think that a Roman shield would stand a better chance against modern gunfire.
 
Hi Sheilawisz,

If I could just comment on the bit about energy transfer from a bullet. All that stuff about people getting hit by shotguns etc and flying backwards out of windows is pure Hollywood. In actual fact the momentum of a bullet travelling at say a thousand kph and hitting you is minimal. Since momentum is mass by velocity you can work it out for yourself. If a bullet ways say twenty grams and travels at a thousand kph, its momentum is the same as if it travelled at 200 kph and weighed a hundred grams, or if it weighed a kilo (the weight of a hand maybe) and travelled at 20 kph. Rather like getting clapped on the back.

The damage done is done by the concentration of momentum on one tiny spot on the body. So if your armour deflects a bullet completely, you'll hardly notice it, force wise.

Again Mythbusters did an epp on this and showed that a pig carcass hanging up barely moved when shot.

Cheers, Greg.
 
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