If you have been looking for the best option for a bulletproof vest, you probably have come across the affordable option of AR500 or AR550 Steel Core Armor plates.  

Some of the nice things about steel core body armor is that it can withstand multiple hits in the same area of the plate. It is not as bulky being anywhere from .25” to .5” as traditional ceramic body armor, which typically is 1” thick. It also is in a price point that enables the modern prepared citizen, security firm or police department to outfit themselves or their employees at a fraction of the cost of other armor options. 

Types of Steel Armor Plates 

If you are new to the game, let’s decode some of the types of steel armor. The AR stands for Abrasion Resistant and the 500 or 550 refers to Brinell hardness of the steel. These steel products are through hardened, meaning that this plate is as hard in the center as it is on the surface. This is important as a surface hardened product would not provide the needed ballistic protection. 

AR500 steel core armor plates are readily available from many manufacturers and they provide Level III protection. We have chosen not to carry this option because for just a very small increase in price AR550 Steel Armor provides you with Level III+ protection and will protect the user from numerous .556 projectiles that the AR500 fails to stop. There are AR600 and AR650 steel options, but the additional hardness makes it prone to cracking due to the inherent stress levels found in these steels after forming. The AR550 is at the perfect hardness level to provide exceptional ballistic coverage while allowing us to apply an ergonomic single press multi curve bend to the steel. 

AR550 Multi-Curve The Best Steel Armor for your Bulletproof Vest

What are the differences between the levels of protection?  

The National Institute of Justice (NIJ) classifies body armor into 5 different threat levels: Level IIA, Level II, Level IIIA, Level III and Level IV based on their ability to stop specified rounds at specified velocities. The NIJ’s current standard is 0101.06 with a pending update to 0101.07 slated to be finalized in 2020.

Caliber Armor Offers Level IIIA Armor Protection & Above  

NIJ Level IIIA is designed to stop .357 Sig FMG FN bullets traveling at a velocity of ~1470 ft/s and .44 Magnum SJHP rounds at a velocity of ~1430 ft/s. The updates for 0101.07 HG2 include testing requirements for 9mm FMJ with a velocity of ~1470 ft/s and changed the .44 MAG test to a JHP (jacketed hollow point) with the same velocity requirements. Our CaliberX Soft Armor panels have been tested to meet both the .06 IIIA and .07 HG2 requirements. 

NIJ Level III rifle plates are designed to stop six spaced hits of 7.62x51mm NATO FMJ M80 at a velocity of ~2780 ft/s. Level III+ is a designation that the industry has adopted to show the capabilities of armor beyond the NIJ Level III testing. This indicates that the plate can withstand higher velocity rounds plus additional threats such as M855 and M193. The NIJ intends to address this in establishing the RF2 category of the 0101.07 standard.  

NIJ Level IV are the highest rated armor plates under the NIJ standards. They are designed to take one hit from an Armor Piercing 30.06 traveling at a velocity of 2880 ft/s. This test will remain the same for the 01010.07 standard.   

Backface Deformation of Steel Body Armor 

Steel body armor provides almost no backface deformation. Backface deformation is the protuberance on the backside of the armor plate that happens from a bullet striking the armor. Even if the bullet does not penetrate the plate it still causes some protrusion, and this is what is measured and is important to pay attention to. The NIJ allows a maximum of 44 mm to pass the Level III hard armor testing requirements. The most that happens with the steel armor is half of that amount. Still, it is always recommended to pair your AR550 steel core body armor with either a soft body armor backer or a trauma pad. This allows you to also be protected from any kinetic energy that is transferred to the plate/vest and then into the user’s body. 

How Much Does Steel Armor Weigh? 

You may be thinking that the AR550 steel armor plates are heavier than some other level III+ armor that is available, but it weighs only slightly more than the cheapest, but more expensive composite counterparts. It’s surprising to most that the thinness of this plate gives the wearer more freedom to move during high stress situations. These plates can easily be kept in the trunk of a car, without fear of temperature related ballistic degradation, for a quick response to an active shooter, or high-risk calls. Unlike ceramic/composite plates, AR550 steel cannot be damaged as easily. They have a much longer shelf life. 

The Best Steel Armor with Spall Fragmentation Coating 

Now onto another very important factor when thinking about purchasing steel body armor. Our AR550 steel armor is strong and when the bullet does not penetrate the armor the projectile fragments generated can ricochet off the face of the armor at a zero to 20-degree angle. You will want to make sure that the armor plates have a spall/fragmentation solution to protect you against this possibility.  

 What is spall? It is the fragmentation that occurs from a bullet on impact. It can cause life-threating injuries to your body. Not all steel plates are created equally. Caliber Armor offers an Anti-Spall coating for steel body armor that encapsulates the fragments. They become trapped between the steel plate and the coating. You can purchase the plates with a standard coating that will keep the plate from rust and corrosion, but it is HIGHLY recommended that you upgrade to a coating that mitigates fragmentation and spall. This is an important feature when choosing steel body armor from us or from any other armor manufacturer.  

Lastly, no body armor plate is bulletproof, only bullet resistant. It’s important to narrow your search and think about what threats you are likely to encounter. You do not want to under prepare and not have the set up that fits your situation.