Posts Tagged ‘spall guards’

Steel has been the material of choice for body armor for centuries, ever since the method for hammering out large, uniform sheets of bloomery iron was rediscovered in the 13th century. Today, advances in steel technology have continued to made this material viable as a protective material.

Steel plates find use in concealable armor as trauma plates, generally having a thickness of 1-3mm. These plates can provide everything from trauma-only, to standalone IIIA protection. Sizes range from 5″ X 8″ to 8″ X 10″. There are a few notable “in between” plates, such as the Second Chance K-30, which will stop 7.62X39 soft core.

Today, most steel plates will be of the “rifle” persuasion. It is important to note that currently, ALL steel rifle plates for personal protection are level III at the highest. Steel plates that will provide level IV (AP) protection are prohibitively heavy for use as wearable armor.

It is important to remember that level III spec calls for protection vs. 6 rounds of M80 ball @ 2750 fps. This means that many round can (and have) been able to defeat level III steel. A few years back, a minor scandal erupted when plates from a well-known manufacturer were found to be easily penetrated by M193 ball above 3000 fps (ironically, I had experienced this same phenomena a week prior to this revelation, and chalked it up to a bad batch of steel. M193 exceeds the shear strength of AR500 steel, and will cause shear-plug failure in the plate. Think a paper hole-puncher, but with steel. The full mechanism of why/how M193 penetrates steel armor is not fully understood, but there are several working theories (to be expounded upon later).

The upshot is, make sure when you buy steel plates, they have either been subjected to additional proof/bench testing, or do not trust them to stop anything but M80 ball.

Steel plates are nearly always sold as “ICW” (In Conjunction With), but I *ALWAYS* advise wearing soft armor behind them. This is for additional blunt force trauma protection, as well as catching any back face spallation (a possibility with all rifle plates).

Steel for rifle armor typically falls into a very specific hardness range, generally 500-600 Brinell (which is VERY hard as far as steel goes). AR500 (“Abrasion Resistant,” 500 Brinell) is the most commonly used commercial steel for rifle armors. It has good uniformity, low cost, and works fairly well.

There are a few other options regarding steel plates, specifically Bainitic steel, and HHS (High Hardness Steel). Bainitic steel utilizes a special heat treating process to produce a particular crystalline phase within steel, called Bainite. This material acts as reinforcement to the crystal lattice of steel, rendering it stronger and tougher than normal quenched/drawn steel plate. At this time, it is still not widely used in personnel armor, though it has found growing use in vehicular armor. Bainitic armor is an excellent choice for personal armor, though the price is typically about 1.5 times higher than normal AR500.

HHS is another option, and describes steel that is hardened to 600 Brinell or above. This allows it to be made thinner than AR500 while having greater ability to stop projectiles. It does have issues with cracking due to its extreme hardness, and is approximately twice as expensive as normal AR500 steel.

Steel plates are extremely durable, often capable of absorbing tens and even hundreds of hits while still retaining ballistic protection properties. With no fragility issues, steel plates are a good choice for use in scenarios calling for extreme ruggedness. With their thin profile (unless coated with a polymer/elastomer finish), they make a good choice for concealable/PSD use. Steel plates are also the most affordable/cost effective rifle armor solution.

One of the biggest drawbacks of running steel plates is their heavy weight. Most 10″ X 12″ steel level III plates weigh around 8 lb. EACH. There is also the issue of rust and corrosion. Finally, as has been discussed before, steel plates suffer from front face splash/spall. Projectiles stopped by the armor will splatter, sending clouds of high velocity core and jacket fragments at a 90 degree angle to the impact. This endangers the wearer’s face, throat, and extremities, and precautions need to be taken by the wearer (https://drmorgear.wordpress.com/products/spall-guards/).

In closing, it is important to evaluate your needs, and determine if steel plates are the correct choice. Next time, we will look at ceramic plates.

Stay safe!

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Steel rifle plates have several advantages, especially for certain applications (PSD, concealed). they are the thinnest profile of all rifle plate styles, are generally very inexpensive, do not suffer from fragility issues inherent with ceramic plates, and handle multiple hits extremely well (some plates have been documented with hundreds of rounds while still retaining their protective qualities).

Interior of 6X6 splash guard after M193 3100 fps impact @ 10 feet on AR500 steel side plate. Non penetrating strike.

With all these advantages, there are several drawbacks, the largest and most pressing being that of front face spall (also known as splash). Spall refers to any ejecta resulting from an impact event. Rear face spall has been an issue mainly with tanks/AFVs for as long as they have been used. In WWI, British and German tank crews suffered casualties from rounds impacting the armor and kicking off shards of the plates at high velocity. Even though the rounds may not have penetrated, damage was still done. The British took advantage of the principle of spall with their development of the HESH round after WWII. This was an explosive shell with a soft head, which, when it hit the enemy vehicle, exploded on the outside. The shock wave blew large chunks of spall off the interior of the vehicle.

Front face spall, or splash, is the result of the projectile disintegrating into a cloud of high velocity fragments. The cloud usually manifests as a primary and secondary conoid of splash, the first being made up of the larger jacket pieces. This usually bounces back at an angle very close to the initial strike. The secondary conoid, which makes up about 80% of the total splash threat, travels primarily along the face of the plate, to exit at close to 90 degrees from the original strike. It is this conoid that presents the greatest threat to life and limb.

Because of how steel rifle plates function, this unfortunate property occurs every time a bullet is successfully stopped. Stopping the round is the purpose of the plate, but up until recently, no consideration was given to keeping the face, throat, and extremities safe from the cloud of cutting fragments. Generally, higher velocity rounds produce more spall (the M193 is a more dangerous round for splash than M80 ball, for instance). The core composition will also play a large role in splash/spall. The M855 produces less spall, due to a larger volume of the core being taken up by a mild steel penetrator. The penetrator is fairly easy to trap with spall mitigation technologies. Close range impacts will obviously pose a greater spall/splash risk than longer distance shots.

Early solutions (still used today) involved plastic or elastomer coatings (in some cases, the same materials used as truck bed liners). These coatings range in thickness from fractions of a millimeter, to nearly half an inch. While effective (at least in the thicker iterations), the material is removed by each successive hit, and in the thinner versions, the spall mitigation is very limited. The main drawbacks involve the thickness of effective coating depth, which mitigates the main point of steel plates (their thin profile), the fact that the coating is permanently removed (which is difficult or impossible to replace). Coated plates often have an offensive, strong chemical odor as well. Coating steel plates is not a bad rust-preventative, but the thinnest coating is recommended.

Other, more recent solutions involve adding metallic components to the plate. While undoubtedly effective at catching splash exiting the sides of the plate, adding MORE metal, MORE weight, and MORE thickness to already heavy plates is not an optimal solution.

Some users have attempted various DIY “solutions,” which usually include haphazard combinations of duct tape, epoxy, gorilla glue, woven aramid or UHMWPE, or brush-on truck bed liner. These solutions are a poor choice, tending to turn steel plates into a messy, ugly, smelly, and above all, ineffective mess. The plates will still stop the rounds as usual, but the splash mitigation is negligible. Because the attempts do not take into account the dynamic nature of an impact, the strong adhesion will couple the facing materials to the plate, resulting in very quick erosion of the homemade guards. This, combined with poor choice of materials (woven Kevlar fabric, or UHMWPE laminate) guarantees failure.

Specially designed slip-on guards utilizing custom engineered/manufactured aramid blend fibers have so far proven to be the best combination of attributes for capturing front face splash/spall. These guards can be removed, swapped between plates, or replaced once used, and are thin, light, and above all, COMFORTABLE. They can be built for ANY steel (or ceramic, for that matter) plate currently extant.

Steel plates can be an excellent choice, but it is vital for end users to be aware of potential safety issues. There are several options for mitigating splash, each with their unique benefits and weaknesses. Above all, ensure you are using adequate splash protection if you choose to run steel rifle plates, and keep your face and extremities safe!

https://drmorgear.wordpress.com/products/spall-guards/

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Steel protective plate are a great option if you are looking for both thin profile and affordable costs, but do have a well known issue that can be hazardous to your health: bullet splash (also known as front-face spall).

Splash is the result of projectiles breaking up on impact with the steel plate (and in fact, is part of the plate doing its job to save your life). This cloud of razor sharp lead and copper poses its own threat to life and limb when exiting the top, bottom, and sides of your plate carrier. This should be taken into consideration when purchasing/using steel plates (and even many ceramic plates).

Other solutions negate the advantages of steel plates, by making them thicker and even heavier. They are also difficult to repair or replace, negating another of steel’s advantages (its durability/multi-hit properties).

Look no further than the D-Rmor Gear Splash guards, custom made and continually improved since 2007.

The D-Rmor Gear Splash/Front Face Spall guards work WITH the steel plate strengths, offering the following notable advantages:

-Thin
-Light
-100% all-fabric construction
-End-user replaceable
-Comfortable
-Effective

In addition, they carry a 100% lifetime guarantee: if they are ever used in a documented duty/self defense situation, they will be repaired or replaced, for the life of the product, fully transferable.

Available in Coyote Brown, and custom made to fit your plates! Check out the link for more information and to get your set today!

https://drmorgear.wordpress.com/products/spall-guards/