Body Armor

[fordnut]

Hey Midnight...Thanks for the Sticky...Very interesting...

Steve

 

[Midnight Raver]

My pleasure, I am here to serve and protect our Forum family! :mrgreen:

I would like to hear some more about the ceramic plates and related stuff like composition and strength. Also, the steel penetrator plates- what kind of hardness are they equal to? I would love to check some out on my friend's Rockwell Hardness test machine! :ugeek:

 

[11B3XCIB]

Midnight, what do you mean steel penetrator plates?


As far as the ceramic plates go, there are two common types, green (boron carbide ceramic) and black (silicon carbide ceramic) plates. They are both required by military standards to take three hits of the caliber specified on the plate itself; the green ones are stronger and are supposed to withstand three direct hits from armor piercing .30-06 (7.62x63) bullets, whereas the black plates are rated for 7.62x51. The plates are wrapped with layers of a sheeted fiber similar to Kevlar, but stronger. I don't know what it is but it's supposed to keep fragments that penetrate the ceramic from passing into the wearer. This is always why they are most effective when used with the soft panels in the vest. The green plates, known as ESAPI (enhanced small arms protective inserts), are heavier than the regular black SAPI plates. I'm on the verge of being able to wear a medium or a large, but usually opt for the medium. My medium green ESAPI plates are 3 pounds heavier for the pair than the medium black SAPIs for my wife's vest. Most vests have the side pockets for small square plates to protect the vitals on the sides...that's an extra 5lbs of armor plating.


I know most of the guys that currently own Class IIIA or IV vests know, but just because a vest with hard plates stops a rifle round or two, doesn't mean the impact won't scramble your guts hard. I go by the assumption that the vest will keep me alive long enough to get to the hospital, because taking a .30-06 round center mass will undoubtedly break ribs, and having bone fragments near your lungs/heart/etc is not good. I saw more than a few SAPI plates take AK-47 hits. The plates stopped the rounds but the bulge in the plate facing the wearer was probably 2.5 inches in diameter and about a 3/4" to 1" protrusion. Another case for using soft panels in conjunction with the plates: I witnessed guy's plate get hit in the side which was a very narrow target(about an inch and an eighth or so in thickness). The round traveled a few inches into the plate and doglegged into the soft panel, tearing through it as well. By that point, the bullet lost most of it's velocity and fortunately barely penetrated the wearer. He was OK. But the soft panels helped prevent further problems...so if you can get them, use them.

 

[armaborealis]

I would like to hear some more about the ceramic plates and related stuff like composition and strength. Also, the steel penetrator plates- what kind of hardness are they equal to? I would love to check some out on my friend's Rockwell Hardness test machine! :ugeek:

Most steel plates are made of Abrasian Resistant Brinnel Toughness 500 (AR500) steel. 3/8" steel plates will NOT stand up to penetrator rounds of any type. SS109 usually cuts through them (especially at closer ranges) and AP 30-06 will breach a 3/8" AR500 plate guaranteed. This is the same steel you see on steel targets at the range, typically--the vulnerability to AP rounds is why ranges frown upon shooting steel plates with ammo like 30-06 AP or green tip 5.56.

As 11B explained, the ceramic plates are usually layered. It is hard to assign a specific Brinnel Toughness to them as each layer has its own properties.

From a consumer point of view, the important factor for "toughness" or "strength" is NIJ rating as described in the first post. The best case is a plate with a NIJ rating. The next best case is a plate built to NIJ specs (but without the backing of the NIJ) or materials that should meet NIJ specs; no guarantees here but you should be ok. The worst case is something built to no spec. The NIJ website has a list of approved manufacturers whose products are certified in independent NIJ lab tests as meeting the spec.

The NIJ Standard (https://www.ncjrs.gov/pdffiles1/nij/223054.pdf) has all the gorey details for exact tolerances, velocity of the test rounds, etc if you want to geek out on it.

UPDATE:
http://www.ar15.com/forums/t_1_5/144393 ... _test.html

There's a link to the "DIY" floor tile armor. My reactions: :evil: :shock: :? :|

 

[John Canuck]

The DIYer at AR15.com used some rhino liner on the back of his test tile. Was that in place of what would normally be soft armor to catch the fragments? That is what's normally done right... Soft armor against the body with plate over top?

 

[11B3XCIB]

The DIYer at AR15.com used some rhino liner on the back of his test tile. Was that in place of what would normally be soft armor to catch the fragments? That is what's normally done right... Soft armor against the body with plate over top?

The hard "ceramic" layers in regular SAPI plates have layers of a kevlar-like material (don't know the official name of it) to help stop the fragmentation and to keep the ceramic compartmentalized. This, in addition to the soft panel, is what provides the protection. So, if anyone wants to buy ceramic plates that aren't brand new, the condition of the wrapping IS important. Also, press your fingers firmly into the plates, front and back, as well as gripping opposing corners and with some force (not too much) attempt to bend or twist. If you hear any crunching, then the plates are compromised and do not buy them.

 

[armaborealis]

The DIYer at AR15.com used some rhino liner on the back of his test tile. Was that in place of what would normally be soft armor to catch the fragments? That is what's normally done right... Soft armor against the body with plate over top?

There are two concerns with hard rifle plates:
1) Spall. This is basically fragments of plate and bullet remnants blowing through the back of the plate into the person. Some rifle plates are rated "level IV with soft 3A vest supporting." That means that you need a soft vest underneath the plate to catch spall.

This is generally not an issue with steel plates; steel plates tend to either "ping" with no serious damage or they are serious compromised. If you've ever shot steel plates at the range then you understand this: you can ping that plate all day with no issues with appropriate ammo, but if you shoot the plate with a 30-06 armor piercing round it will go through like a knife through butter (and the range gets mad at you...).

It is more of an issue with ceramic plates, especially legacy designs. Ceramic crumbles when hit and a kevlar spallguard can catch the low-velocity ceramic and bullet fragments blowing out the back. When you buy commercial plates, they will tell you if you need a doft 3A vest supporting the plate to get the full protective value. Most commercial plates these days do not require a 3A vest supporting but a few do. If you "DIY" with floor tiles from Lowe's then I'd definitely want to put some sort of spall guard behind it, although in very limited testing it looks like the back of the tiles are not compromised too badly.

2) Fragmentation. This is fragments of the bullet spraying off the front surface of the plate and skipping into the person's groin, neck, and arms.

This is a big problem with the steel plates. This is why most ranges that let you shoot steel targets require you to stay back a safe distance; the bullets will hit the plates, fragment, and skip/richochet all over. The project you are seeing at AR-15.com uses (1) herculiner or (2) kevlar wrap or (3) HDPE cutting board (4) a mixture of these techniques or (5) commercially applied LINEX or RhinoLiner to solve this problem. The goal is to trap any richochets or other frag.

It is not a huge issue with ceramic plates, although some designs like SAPI do layer Kevlar and ceramics because they are built by materials scientists and cost $600+.

 

[armaborealis]

The Target Man is now offering 8x10 coated plates for $130.
http://thetargetman.com/?product=sparta ... protection

RedCatTactical still has a few vests available for $30 each.

Doing the math you can put together a "his" set AND a "hers" set of basic rifle plates and carriers, out the door, for about $350 total. It doesn't get much cheaper than that for two armor setups.

 

[Underdude]

I went with US Palm. Level 3A soft panels front and rear, weighs slightly more than 3 lbs, and just around $300 delivered.

 

[slidewayz240sx]

I use a Crye Precision JPC for work.

 

[Avtomat-Acolyte]

That flag looks weird. Who made it?

Also, what's up with the three black dots?

 

[slidewayz240sx]

That flag looks weird. Who made it?

Also, what's up with the three black dots?

I found the flag laying around my unit and just had it laying around in my bag after. It's an IR flag non the less. As far as the dot, it was just some velcro that came with it. They arent on it anymore. This photo was back when I first bought the carrier. It now has the Crye side plater carriers. I like this compared to normal carriers because its lightweight and rides high enough to allow the wear of a a battle belt taking a lot of the weight off of my shoulders.

 

[rum4]

Anyone using AR500 armor?