Penetration of .223/5.56mm rounds

[chuft]

Apologies if this kind of thing has been debated to death before.

I was watching "King Arthur" last night, with guys running around in chainmail and steel breastplates, and I couldn't help but wonder "What would happen if somebody wearing metal armor like that got shot with a round from my AR-15?"

Historically, I know that people gave up wearing armor altogether thanks first to the longbow and eventually to early, crude guns, which could penetrate any armor. One would think today's battlefield rifles could do a much better job than the crude weapons of the 15th and 16th centuries. And in fact people have told me modern rifle rounds can penetrate Kevlar unless there is a ceramic plate in there - that Kevlar is only good against pistols, shrapnel etc.

Yet, I have been hearing tales of 5.56mm rounds bounching off, or at least failing to penetrate, enemies in Afghanistan etc. wearing nothing heavier than winter clothes, and the U.S. army thinking of moving to a larger caliber as a result.

Something doesn't seem right. Does the Army's main battle rifle have less penetration power than an English longbow from the 15th century? If winter clothes could stop a 5.56mm round I would think Kevlar would do it easily.

 

[griz]

ANY 223 round, FMJ, HP, anything, would easily slice through the thin sheet metal of medival armour. I think the tales of the 223 failing to stop people are not from bouncing off but from overpenetration with little damage.

 

[444]

I swear, some of the stuff I read on the internet is killing me.
What you need to do is take your AR15 out and do a little testing for yourself. Then come back and we can discuss rounds bouncing off clothing.

 

[uglygun]

Here's a picture of a steel plate that is 1 1/4 inches in thickness.

The larger craters towards the top of the plate were by a 190grn 300WinMag loading at 2900fps, the cluster of smaller craters to the upper right corner were done with 223Remington at around 3100fps.

This steel plate is above "mild steel" in hardness but isn't quite as highly rated as hardened armour plate. The old armour of the middle ages would hardly stand up to a 223Rem at 3000+fps, much less anything else around 1100fps or faster.

 

[Texas Gunman]

Here a link with alot of useful info on 223/556.

http://www.ammo-oracle.com/body.htm

I like using SS109 & M885 and Wolf ammo for plinking.

TG

 

[benEzra]

uglygun,

Where?

 

[spacemanspiff]

duhh! its one of those 'magic eye' pictures! i can see it just fine.

(its a schooner.

no stupid, its a sailboat!)

 

[uglygun]

Opps, here's the pic.

Was in a hurry, got home early from work so I was off to the gunshop to grab some reloading supplies.

 

[MagnumCaliber357]

Mbr???

not to nit pick but an M16 is not a main battle rifle. MBR have to be chambered for a larger round the 5.56, like a .308. Its alaways good to know your terms

 

[g56]

Isn't 7.62 NATO much better for long range penetration than 5.56?

The SS-109 (5.56) can penetrate the 3.45mm standard NATO steel plate to 640 meters, while the 7.62mm ball can only penetrate it to 620 meters. The U. S. steel helmet penetration results are even more impressive as the SS-109 can penetrate it up to 1,300 meters, while the 7.62mm ball cannot penetrate it beyond 800 meters.

 

[chuft]

>I like using SS109 & M885 and Wolf ammo for plinking.

I have been using Wolf for plinking with my Olympic Arms AR-15, but it jams fairly frequently - probably 2 or 3 rounds out of every 100. Being new to this I did not know if it was the fault of the ammo, the gun, the magazine, or something else.

Now I am reading this business about melting lacquer on the Olympic site

http://www.olyarms.com/index2.php?page=ammowarning

and about melting sealant (on this site in various threads).

Am I hosed? It sounds like Wolf leaves some kind of nasty residue behind when the chamber gets heated, which then cools down and coats the inside of the chamber. Is there any way to get that stuff out of there?

 

[natedog]

The SS-109 (5.56) can penetrate the 3.45mm standard NATO steel plate to 640 meters, while the 7.62mm ball can only penetrate it to 620 meters. The U. S. steel helmet penetration results are even more impressive as the SS-109 can penetrate it up to 1,300 meters, while the 7.62mm ball cannot penetrate it beyond 800 meters.

That isn't really a fair comparison, as the SS-109 has a hardened steel penetrator, while the M-80 7.62mm round is just copper-jacketed lead.

 

[kaferhaus]

MBR have to be chambered for a larger round the 5.56, like a .308. Its alaways good to know your terms

MBR is an "internet commando"/gun rag term that means nothing... I was in the Army for 30yrs and never heard the term. It's "standard issue rifle", whether it's an M14 or a mouse gun and I toted both for more miles than I care to remember.

Mil-spec 308s make bigger holes but don't fragment near as well as the 5.56, and often pass clean through the target. they're heavier, you can't carry as much ammo, they're harder to shoot accurately, etc. etc.

I've seen bad guys shot with both and a poorly placed 308 is no more effective than a poorly placed 5.56. A properly placed 5.56 is just as or more effective than a properly placed 7.62x51.

This argument is ages old and some guys will just never believe that a high speed light weight fragmenting bullet will do a tremendous amount of damage to what ever it hits

Heat of action battlefield claims of poor performing weapons and ammunition are often proven false when the facts are properly investigated, it happened in vietnam, it happened in grenada and it happened in the first gulf war just as it is now.

Watch some the Irag footage of the bad guys getting popped by 5.56s from a couple hundred yards away and dropping like sacks of potatoes..

There's video floating around also of some engagements in Afganistan that show the same thing.

The M16 was not designed to be lethal at long range. It was designed to be "effective" at 350meters. Effective means a well placed hit will remove the combatant from further effective resistance.

Most combat involving rifle fire since the end of WWI has been at ranges of 200yds or less, most of the time much less.

Rifle engagements at ranges further than 200yds are VERY uncommon.

A tired, scared, pumped full of adrenaline soldier rarely kills an enemy by AIMED rifle fire at ranges outside 100M.

The vast majority of casualties in this war as in every one since the civil war are not the result of gunfire. They're the result of mines, artillery, mortar and other indirect fire (road side bombs). Very few of our soldiers have fallen to gunfire in either Irag or Afganistan.

 

[Texas Gunman]

chuft, Wolf ammo works great in most AR15s, that is chambered for 556,it also work great in ones chambered for reg 223 chamber,match grade chambers are usely the ones who has problems with Wolf ammo,also some none chrome chambers has problems after barrel heats up.

The old Wolf ammo had the laquer,but the new stuff doesnt, that being said old & new Wolf worked great in both my bushmasters.

TG

 

[chuft]

Not sure I understand what you're saying Texas Gunman. Did you read the Olympic Arms page I posted the link to? They say not to use Wolf and they are the manufacturer of my gun. Is there something wrong with Olympic AR-15's?

 

[Feanaro]

If chain/scale/plate armor would stop a rifle bullet don't you think ONE army would be using it? If heavy clothing stopped 5.56, why aren't the Towelheads wearing nothing but? I'm not a follower of the 5.56 cartridge but the idea that it won't go through clothing or a suit of armor is just silly.

G56: from the same article.

These comparisons however, do not consider the fact that the SS-109 uses a semi-armor piercing, steel-cored projectile, while the 7.62mm ball uses a relatively soft antipersonnel, lead-cored projectile. A semi-armor piercing 7.62mm caliber projectile, using second generation technology as the SS-109, would easily outperform the smaller SS-109 projectile in penetration tests at all ranges. With respect to barrier and fortification penetration tests, the 7.62mm ball projectile can consistently penetrate two test building blocks, while the SS-109 semi-armor piercing projectile cannot penetrate a single block.

Now, if .308 bullet were made with the same thin jackets* as most 5.56, y'all would have to buy .308 rifles and throw them ineffective poodle shooters away.

* http://home.snafu.de/l.moeller/wund8.jpg

Not sure I understand what you're saying Texas Gunman. Did you read the Olympic Arms page I posted the link to? They say not to use Wolf and they are the manufacturer of my gun. Is there something wrong with Olympic AR-15's?

Reload for any of your guns? Most manufacturers recommend against usin' 'em. Gonna' stop reloadin'? I bet not. Some people have trouble with Wolf. If so, don't use it. If it works, it sure is cheap plinkin' ammo.

 

[uglygun]

Most people assume the steel penetrator tip in the SS109 bullet helps it at all distances and it's not quite an accurate assessment.


The M193 loading with 55grn all lead construction bullet actually bests the 62grn M855/SS109 at closer distances where the velocity advantage is still in the lighter 55grn round's favor. Against some varieties of harder materials, the speed is what counts and the 55grn bullet impacting at a good 150-200fps faster makes a difference where as the little 5grns of steel in the 62grn bullet's tip doesn't help overcome the velocity disadvantage.

Where the 62grn SS109 comes into it's own is farther down range where it is retaining more velocity and the balance/scales have tipped into the favor of the heavier M855 round. And even then, the round was never meant to be an "armour piercing" round with respect to true "armour" such as hard materials. It's a noodle popper(yeah, noodle, not poodle) in that it's designed to defeat layers of kevlar or "soft armour".

As for the whole suit of armour stuff, might as well be tin foil with respect to modern chamberings.

 

[Byron]

Kaferhaus,well said.I used the 16 and the M193 round in 68-69 as a 20 year old infantryman.The M193 is very destructive.My rifle never jammed. Byron