Archive for the ‘Body Armor The Good The Bad and The Ugly’ Category

Modern armor leans rather heavily on a class of materials known as ceramics. Man has been developing and using ceramics since antiquity, and they still play a vital role (some would say even more so now) in the 21st century.

But instead of amphorae to hold wine, olive oil, or other bulk trade goods, ceramics are used in more demanding applications, where extreme heat, pressure, abrasion, and corrosion resistance are critical.

For applications in body armor, ceramics must exhibit several seemingly contradictory attributes, of which four are absolutely critical. They are:

Bulk Density: This translates into how heavy a ceramic is for a given volume. The lower the number, the better.

Hardness: This is a ceramic’s resistance to indentation. Harder is better, especially when facing tungsten carbide core threat projectiles.

Fracture Toughness: How resistant to crack formation and propagation a ceramic is. The higher the number, the more suitable as armor.

Modulus of Elasticity (Also known as Young’s Modulus): This describes how stiff a material is  (elastic deformation). The higher the number, the stiffer it is.

There is also another vital attribute to consider, which is cost. There are several ceramics that would be considered “ideal,” but are disqualified due to prohibitive cost. I have provided the attributes below, as well as a numerical rating from 1 to 3 (1 being least efficient, 3 being most efficient). Below a usable threshold will result in a 0. This will allow us to see how each ceramic stacks up.

The three primary technical ceramics that account for 95% of the ceramic armor currently used (personnel and vehicular) are:

Aluminum Oxide (AKA Alumina, Al2O3)

Silicon Carbide (AKA Carborundum, SiC)

Boron Carbide (AKA Black Diamond, B4C)

The traits and attributes are as follows:

Al2O3-

Bulk Density (99.5% grade): 3.90 g/cm3 (1, heavy)

Hardness: ~1400-2000 Knoop (Kg/mm2) (2, low-medium hardness)

Fracture toughness: 4.5 (2.5, very good)

Elastic Modulus: 393 (1.5, low)

Cost: $ (affordable)

Overall rating: 1.9 out of 3

SiC-

Bulk Density (Sintered): 3.21 g/cm3 (2.5, medium weight)

Hardness: 2800  Knoop (Kg/mm2) (2.5 high hardness)

Fracture Toughness: 4 (2, good)

Elastic Modulus: 475 (2.5 medium-high)

Cost: $$ (expensive)

Overall rating: 2.3 out of 3

B4C-

Bulk Density (Hot Pressed): 2.51 g/cm3 (3,extremely light)

Hardness: 3500 Knoop (Kg/mm2) (3,extremely hard)

Fracture Toughness: 2.6 (1,low)*

Elastic Modulus: 675 (3,extremely high)

Cost: $$$ (extremely expensive)

Overall rating: 2.2 out of 3

So, as can be seen, there are numerous factors involved. While Boron Carbide is the hardest of the commonly used ballistic ceramics, it is not the best overall. Silicon Carbide takes the honors, having the best combination of factors. If weight is paramount, B4C is the leader.

By comparison, the following are the attributes for Silicon Nitride, an “ideal” ceramic for ballistic applications:

SiN-

Bulk Density: 3.31 g/cm3 (2.3, medium heavy)

Hardness: 2200 Knoop (Kg/mm2) (2.3, medium hardness)

Fracture Toughness: 7 (3, extremely high)

Elastic Modulus: 317 (1.5, low)

Cost: $$$$ (prohibitively expensive)

Overall rating: 1.82

And the attributes for fused silica (SiO2, glass)-

Bulk Density: 2.2gm/cm3 (3, very light)

Hardness: 600 Knoop (Kg/mm2) (0, below usable threshold)

Fracture Toughness: 1 (0, below usable threshold)

Elastic Modulus: 73 (0, below usable threshold)

Cost: $ (very inexpensive)

Overall rating: 1.2

So, as can be seen, multiple factors are in play when selecting optimal ceramics for ballistic use. Looking at just one, or even two will not give a complete picture.

Which is why most ceramic armor for rifle and larger caliber applications is either Alumina (most effective ceramic for the money), or Silicon Carbide (best performer for the money).

And until revolutionary advances are made in the field of nanotechnology and technical ceramics, the three main materials listed above will be soldiering on for the forseeable future.

*Special note about Boron Carbide- B4C undergoes what is known as “amorphization” under impact loading. In layman’s terms, the crystalline structure of the Boron Carbide is converted to a glassy (amorphous) structure when impacted at high speed. This causes a tremendous loss of strength. The reasons for this impact-loading loss of strength is still not fully understood, and ongoing research is attempting to remedy it. Neither Al2O3 nor SiC undergoes this transition.

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Recently I have had several inquiries about GRP (Glass Reinforced Polymer, or “fiberglass”) armor. It’s important to review this material, as it is becoming more prevalent in the armoring world. It has advantages in certain applications, but is totally unsuitable in others.

GRP has been around for a while. Some of the first body armor and vehicular armor utilized this material. It is comprised of woven, large-denier S-Glass fibers in a resin (usually epoxy, but often polyester or similar). The panels are rigid, and range from a few millimeters to over an inch thick.

In applications such as structural hardening and vehicular armoring, this material is very suitable, as S-Glass is much less expensive than either Aramid or UHMWPE reinforcement. It also has excellent environmental stability, able to withstand long periods of exposure to the elements without appreciable degradation or maintenance.

Recently however, this material has begun to be re-introduced as body armor, either in standalone applications as “handgun resistant” plates, or as the backing component to ceramic rifle plates. In my experience, this material is to be avoided as personal armor.

First and foremost, during a ballistic event, glass fibers are thrown off at high velocity. Unlike Aramid fibers, these can embed themselves in the wearer, requiring exploratory surgery to remove (since glass fibers do not show up on X-ray). A projectile defeat of the plate will pull additional secondary glass fiber projectiles into the wound, complicating it.

Secondly, in handling. This material often has “slivers” or “splinters” of glass fibers standing proud from the surface. These are a non-inconsequential hazard.

Finally, GRP armor is nearly twice as heavy as an equivalent Aramid panel, and three times the weight of UHMWPE for its protection.

My advice would be to spend a little extra to ensure you are getting either Aramid or UHMWPE plates, and avoid rifle plates that specify GRP backing.

Over the past six months, there has been a great deal of both excitement, and lately concern, regarding the Armour Wear AR680 plate. Touted as a “level III+” plate, it is claimed to stop the extremely dangerous M193 high-velocity threat.

In the past few months, extremely un-scientific tests on Youtube seemed to “prove” that it was prone to failure when shot by M193 @ 3200 fps.

Unfortunately, Armour Wear did not originally release a very scientific test video themselves.

At this juncture, I have not seen proof either way, either validating or disproving the efficacy of the AR680 plates. Simply because both the proponents (the company in particular) and the detractors (youtube channel) did not take the small amount of extra time and effort to arrange a proper test.

A proper test is *NOT*:

Setting up a bunch of plates on a berm at a 45 degree angle and blazing away willy-nilly.
Setting up a huge sheet of the steel (again, at a range), and (again), blazing away.
Clamping the plate to a rigid fixture, with no backing, and shooting it.

To properly test body armor, hard or soft, requires the use of a backing. The NIJ specifies no.1 Roma Plastalina modeling clay. Any semi-flexible backing will do, as long as it is close in consistency to a human body. The reason for this is two-fold: first, to be able to determine how much energy (backface deformation) is being imparted to the wearer. Secondly (and for the purpose of this post, more importantly), to mimic the physics of the armor being worn.

A plate that is clamped to a rigid fixture will behave differently than one that is resting on a flexible surface. A rigid plate will have no give, and the round will transfer more energy to the plate. With a proper backing, the initial impact will be reduced ever so slightly.

For some armor (soft armor in particular) this will make the difference between complete penetration, and performing as designed (setting a soft armor vest against a plywood or other hard surface enables it to be penetrated with ease). This will also have relevance with hard armor, especially if it is near its failure threshold.

In the same way, propping a plate at an angle will allow it to stop far more than at 0 degrees of obliquity. MBT armor is sloped for this same reason.

As a result of the above, I will be performing a scientific (or at least, much more so than has been performed so far) comparitive shoot test on the Armour Wear AR680 and Maingun Patriot 2 Advance plates. I had contacted Spartan Armor in an attempt to source one of their level III+ plates to include in the test, but have not heard back from them.

It is my hope that this test will settle any arguments once and for all regarding M193 high velocity protection. Stay tuned!

For those that have read my Body Armor: The Good, The Bad, The Ugly series, you know that identifying the composition of your soft armor ballistic package is of the utmost importance.

Unfortunately, without examples of what each of the multitude of materials looks like, it becomes a virtually impossible task. With certain materials posing a very real risk of bodily harm or even death when used in soft armor, proper and timely identification becomes even more vital.

My Version 1 Armor Material Field I.D. Guide was a solution to that problem. And now, by popular demand, Version 2.1 incorporates improvements and enhancements over and above the original.

IMGP0563

IMGP0564

The Guide is a pack of rugged, compact laminated cards, packed full of important information and stats on all the most common body armor materials, from first generation woven aramid, all the way up to the most cutting-edge fifth-gen “wovenates.” In addition, each card contains an actual swatch of the material in question, to make identification simple.

Available in limited quantity, the D-Rmor Gear Armor Material Field I.D. Guide is only $15 shipped anywhere in CONUS. Get yours today!

https://drmorgear.wordpress.com/d-rmor-gear-armor-material-field-i-d-guide-v2-1/

Anyone who has read my blog for any length of time is probably aware of my opinion of laminates (not great). UHMWPE laminates are not recommended for use in soft armor at all (due to heat degradation and contact-shot issues), while Aramid based laminates have problems with delamination, heat/sweat retention, and similar difficulties with muzzle-contact shots.

Despite several generations of laminates being produced since the original iteration was released back in the 90’s, the problems remained- limited lifespan of the armor package due to creeping edge delamination, feeling like you were swathed in plastic shrink-wrap (which, essentially you were), and poor performance against shots that allowed hot muzzle blast to melt the plastic film holding the unidirectional layers together.

These glaring deficiencies have prompted the major developers of aramid-based ballistic materials, Teijin and DuPont, to create a new generation of materials that attempt to combine the admitted advantages of laminates (extremely thin ballistic packages, greater flexibility, good edge and high angle hit resistance) with the known advantages of woven aramids (breathability, no delamination worries, greater ballistic package longevity).

These efforts led to the debut of DuPont’s Kevlar XP in 2009, and Teijin’s Twaron LFT SB1 in 2012 and LFT SB1+ in 2013. These materials utilize a hybrid of both woven and laminate technology, and so the term “wovenates” is best used to describe them. Rather than using the traditional, and flawed method of encapsulating with a plastic film, both companies chose to use a very flexible resin to saturate the fibers. This obviates delamination, and also allows for a much thinner overall ballistic package. The two different designs (XP and SB1) rely upon tried and true aramid fibers arranged in unique fashion, similar to standard woven Kevlar fabric. This combination of attributes makes for a highly flexible, yet durable material.

Additionally, these materials have been tested and shown to provide significant reduction in both weight, and backface deformation (particularly SB1+). Sweat management is much better than previous laminates, due to the construction of these materials.

Examination of used ballistic packages made with these materials do not exhibit delamination or degradation even after several years of heavy use, and testing shows that they still provide the same level of protection that they started with.

At this time, I can endorse the use of these materials (Kevlar XP and Twaron SB1/SB1+) as viable options for personal protective gear, comparable to woven Aramids. I have not evaluated their effectiveness against contact shots, but will do so in the near future.

Stay tuned for more information!

Steel rifle plates are an affordable and effective option for those looking for rifle-round protection, as well as possessing the twin benefits of extreme durability and thin profile. As I have mentioned in previous iterations of TGTBTU, they represent a viable solution to everyone from LEOs to the prepared American.

Their one main drawback, aside from their weight (on average, higher than either ceramic or UHMWPE) was their susceptibility to the very common M193 threat. This round, in general, could be counted on to Swiss-cheese garden variety AR500 steel, if shot at or above 3000 fps (a disturbing fact that has been well-known since 2007).

It has been known to me for some time that there was a solution, but it warranted further investigation. That solution was/is Ultra Hard Steel. Most armor-rated steel possesses a Brinell hardness (BHN) of around 480-510 (the well known “AR500”). This standard steel, used for target gongs, and of late, rifle plates, is hard, but not hard/tough enough to stop M193 at high velocity. This round, due to its energy and small frontal profile, “punches” out cylinders of material, a mode known as “shear-plug failure.” UHS, by comparison, possesses extreme hardness, almost approaching that of ceramic (anywhere from 650-720 BHN).

This steel will easily stop M80 ball, M855, and M193 in 5mm thickness, meaning that rifle plates made with this material are truly triple-threat capable (these three rounds, along with 7.62X39 constituting the main threat spectrum most wearers need concern themselves with both in and OCONUS).

A new company called Armor Wear has become the first to bring an UHS plate to market, and my congratulations to them:

https://armour-wear.com/shop/all/ar680-steel-plate/

Calling their plates “AR680,” in reference to the BHN, these plates can be fully expected to stop M193 at a remarkable 3300 fps. The price point is $134 per plate, which although higher than regular AR500, is very reasonable given the exceptional capabilities. Weight for uncoated plates is 6.2 lb., which is the same or close to some ceramic plates on the market! With the build-up Line-X coating, the weight rises to 7.4 lb. per plate, but that is still a vast improvement over the older, less-effective AR500.

With this sea-change in the nature of steel rifle plates, I can now unhesitatingly recommend steel as every bit as good as ceramic and UHMWPE if weight is not a primary concern. From this point forward, UHS should be considered “best practices” if one is considering steel rifle plates.

Because bullets and fragments are not the only threats out there, current technology has developed ways of dealing with some of the oldest weapons known: sharpy pointy things.

Ballistic armor is designed to stop high velocity projectiles, while cut/stab armor is designed to stop very slow (relatively!), sharp and pointed objects from cutting/piercing the wearer’s skin.

This type of armor is a continuation of the most ancient forms of personal armor, which has seen the use of bone, fabric, leather, and finally metal. It is interesting that the current state of technology has returned to the use of fabric as the primary defense against thrusting and cutting implements.

As it has been for millenia, there are always trade-offs in terms of protection vs. weight/concealability. The most protective suits, while they can be made with extremely good ergonomics, will tend tno be hotter, heavier, and far from low-profile. Semi-rigid and rigid armors, which include forms of metal mesh (traditional “maille”), interlocking articulated plates (metal or metal/composite), lamellar, or solid plates are very efficient at stopping cuts and thrusts. Their weight and heat burden tend to be fairly high. Materials range from stainless steel, titanium, to rigid para-aramid (Kevlar/Twaron).

Fabric materials are currently used in the majority of concealable stab/cut vests. These include the familiar materials Kevlar, Twaron, and Spectra. As before, UHMWPE laminates should be eschewed, even though they may provide better numbers in terms of weight. The known weaknesses of this material outweigh any benefits. Generally, the Para-Aramids are woven, similar to their ballistic counterparts, but are much tighter weave. This is to prevent spikes from pushing the fibers aside. The number of layers is directly proportional to the protection levels, which are rated in a similar way to ballistic standards. They are:

KR1/SP1 (Knife Resistant Level I/Spike Protection Level I) – Lowest level, resists knife thrusts and spike stabs at 24J up to 36J
KR2/SP2 (Knife Resistant Level II/Spike Protection Level II) Medium level, resists knife thrusts and spike stabs at 33J up to 50J
KR3/SP3 (Knife Resistant Level III/Spike Protection Level III) High Level, resists knife thrusts and spike stabs at 43J up to 65J

Level I armor is generally the best choice if wearing for long periods and/or concealed.

Level II is a good compromise between concealability and protection.

Level III is for short periods of time, and is not generally concealable.

The test protocol involves dropping a weighted sabot (weighing about four and a half pounds) from different heights with the test blade or spike onto the armor sample. Up to 7mm of penetration is allowed at the minimum force, and up to 20mm at the maximum force. Any greater penetration at either energy will fail the armor. There is *no* penetration permitted for the spike test at any energy level. A single sample armor may be subjected to over 30 drops, with no overpenetration permitted.

I am sure a lot of folks are wondering about how well knife/stab armor performs against bullets. The answer is “not as well as a dedicated ballistic vest.” K/S armor is engineered towards a very different threat compared to handgun rounds. Knives, spikes, and syringes have a very small frontal area compared with handgun bullets, and as such, require different materials and construction methods to be used. There are dual and triple rated vests (ballistic + knife and ballistic + knife + spike), but they are generally VERY expensive, and heavier/thicker than dedicated armors. If you absolutely have to protect against multiple threat types, try to wear before purchasing to ensure it is comfortable.

So to summarize: while there is some overlap in the capabilities of bullet resistant vests to stop blades, and knife/stab armor to stop bullets, unless they are specifically engineered to do so, don’t rely on them to protect you from all threats.

In several of my posts, I mention that while UHMWPE UD armor is an excellent choice for certain applications, and has material advantages over woven or laminate Aramid ballistic fabrics (higher potential V50, positive buoyancy, UV resistant, waterproof), it suffers from several glaring weaknesses (degrades to complete ineffectiveness above 170F, no breathability, delaminates/curls, and is WEAK AGAINST CONTACT SHOTS).

It is important to reiterate that last weakness: a large number (if not the majority) of self-defense and duty scenarios take place at 0-5 feet, where contact shots are a high likelihood. Woven Kevlar soft armor has shown to provide EXTREMELY good protection against contact shots (defined as the muzzle of the weapon being in physical contact with the vest or armor panel). The point at which Kevlar chars is around 500F, and it will retain its strength below this temperature.

The failure mechanism for UHMWPE in contact shots is the high temperature propellant gases that exit the muzzle microseconds after the bullet. These gases heat the area surrounding the muzzle and bullet path, and cause the laminate to melt/denature. This allows the bullet to penetrate much further than would normally be possible. In the case of large caliber revolvers (with a large muzzle blast footprint), this can allow the round to completely defeat the vest.

Test Round

Test Round

For the sake of the test, the round chosen was the .357 Magnum, rather than a .44 Magnum, as I wanted to see if the (relatively!) more modest caliber would still defeat the level II ballistic panel. The panel consisted of 15 layers of Dyneema SB-38. Round chosen was Hornady Custom 158 gr. XTP @ 1250 fps muzzle velocity, from 6″ barrel. The level II panel is specced to stop an equivalent round.

Test Panel

Test Panel

Backing

Backing

The panel was placed against a backing material consisting of 8 layers of bubble wrap, covered in a dish towel. In retrospect, this was probably a bit too “springy,” giving the panel an advantage by permitting it to move away from the hot muzzle blast faster than if the armor was being worn.

Test Panel Ready To Shoot

Test Panel Ready To Shoot

The test panel and backing were placed upon the ground, and the muzzle pressed firmly (but not forcefully) against the surface. The round was discharged into the center of the panel.

First shot

First shot

First shot, through the backing

First shot, through the backing

First shot, rear of panel...

First shot, rear of panel…

The panel was defeated, showing that the muzzle blast had melted a moderately large area around the point of contact. The round penetrated the backing and buried itself into the dirt (as shown).

To verify, a second round was fired into the lower left area of the panel (away from the heat affected zone of the first round). The second round performed identically, burying itself into the dirt beneath the panel.

Second Contact Shot

Second Contact Shot

Second Round, showing penetration

Second Round, showing penetration

Second shot, layers peeled back

Second shot, layers peeled back

Second shot, showing exit into backing...

Second shot, showing exit into backing…

...And into the dirt

…And into the dirt

Conclusions:

The results of the test shows that UD UHMWPE laminates are at risk vs. contact shots. Heat from the muzzle gases (especially medium to large caliber revolvers) “blazes a trail” so to speak, for the round to penetrate further than it normally would.

Well, apparently my last post was a little too pointed, as it has already garnered a response. Unfortunately, the response was based on the notion that I am a “supporter” of steel plates over ceramic.

If anyone can show, unequivocally, where I have ever written that steel plates are completely “superior” to ceramic plates, they get a free rock sling.

This is why reading comprehension is so vital, and yet found lacking in most interactions.

Please re-read The Good, The Bad, and The Ugly. No dogs are selected to fight. Just the basic facts about each choice.

I think the problem is that I did not “bash” steel enough compared to ceramic. I will not do so. I make the assumption that all my readers wear big-boy pants, and when I say that steel is HEAVY for type, and experiences FRONT FACE SPALL, they are intelligent enough to weigh these drawbacks versus the advantages. I am not interested in impugning their intellect, or questioning their “seriousness.”

Furthermore, steel is out there. People are using it and will continue to use it. Arguing against something that has such major market penetration is tantamount to arguing against certain computer operating systems, even though we know they have flaws. Instead of lambasting people for their choices, I choose to do something to make that choice safer, just as you can improve your experience with the aforementioned OS with some simple, minor changes. When steel ceases to be used for personal protective gear, so be it.

Finally, it is amusing to me that the response came so quickly- I was not directing it at anyone in particular, certainly not at the guy that responded (inadvertent recon by fire?), but it made my point very clearly. Making a fully informed choice is not purchasing a stake in a fertilizer concern.

The internets are full of pi**ing matches. I am not going to engage in any here.

Let me reiterate, in case the above was too verbose:

Steel= GOOD!
Ceramic= GOOD!
UHMWPE= GOOD!

They will all stop centerfire rifle rounds. They all cost varying amounts of money. They all have varying material properties. They are not all the same. Pick one, or two, or all. Use them. Train with them.

Providing objective evaluations on these different material options does not place me into any “faction.” Providing enhancements to any or all of them does not place me into any “faction.” Except perhaps the “faction” that wants to make any and all armor better and safer.

As Musashi said, know your tools, their strengths and weaknesses. If you do, you will use anything to the fullest extent.

It seems that over the past few years there is a growing factionalism and hardening of opinions within the shooting/gear community, and more specifically, regarding choices of armor.

Lately, there have been several very strong pieces written about the complete unsuitability of steel rifle plates, and that ceramic is the *only* viable choice for those who are “serious” about protecting themselves.

While I appreciate an impassioned, well-written argument as much as the next guy, I think that such rigid positions do a disservice to those seeking an honest comprehension of the various self-protection options.

The current “hot topic” of debate seems to be steel vs. ceramic, with proponents of the latter insisting that steel rifle plates have no place whatsoever in the self-protection arena. Ceramic, they argue, is far superior in every way, and steel is nothing but heavy, dangerous, useless dead weight.

One of the primary reasons I started this site was to provide balanced, reasoned, and honest evaluations of various materials and armors that are out there. While it is true that steel has known issues and challenges, ceramic is not perfect, and downplaying these considerations (COST and fragility being the two biggest), do not make them go away. While it is true that there are VERY affordable ceramic plates (the Midwest Guardian IV being at the very top of the list), and also true that ceramic plates are not porcelain dolls, to ignore the fact that EVERY armor (throughout history) is a compromise of many different factors is to ignore reality.

Most people purchase steel plates because they are the most affordable option. They are also hands down the most durable, and if someone has honestly evaluated their needs, and found that they don’t want to worry about their logistics tail (replacing a broken ceramic plate) and would rather allocate the difference in cost to other areas (training/ammo/etc.), then deriding them for their “inferior” choice is not going to alter their decision. It is true that steel plates are heavy for type, and do have issues with front face splash (albeit less of an issue with proper spall-mitigation technologies). But for someone that wants an inexpensive, demonstrably effective way of keeping centerfire rifle rounds out of their vitals, without breaking the bank, steel works.

I advocate selecting the correct tool for the job, and will say right now that not everyone NEEDS a sub-4.5lb. level IV ceramic plate for their particular task. While it is a “nice to have,” most cannot justify the commensurate high cost associated with the “best” armor.

In conclusion, I recommend folks re-read the “Good, Bad, Ugly” posts again. Each of the three major plate types has pros and cons- there is no BEST option for all people or all roles. Know your needs, and know the options. Strong opinions are good, but they should be tempered by the realization that not everyone needs/wants the same thing.