How does a bulletproof vest work?

Have you ever wondered how a simple vest can stop high caliber bullets? Perhaps its mode of operation is completely unknown to you?

Indeed, when you realize how fast bullets can be, you can only marvel at such a feat. However, the performance of bulletproof vests has proven its effectiveness over the years. You just need to learn more about the materials required in their manufacture and the way in which the different materials that compose them are used in order to understand how a simple protective jacket manages to stop projectiles as fierce and deadly as bullets.

In this article, we will study:

• The composition of the bulletproof vest
• How Kevlar works
• How to recognize a good bulletproof vest

Let’s get started without further ado!

What is bulletproof vest made of?

It goes without saying that body armor is, above all, armor. Of course, unlike those of ancient times, where men fought with spears and swords, modern armor must be able to absorb projectiles at extreme velocity. We are talking here about at least pistol bullets whose average speed is between 250 and 500 m/s.

Moreover, it is important to note that bulletproof vests made their most significant evolution quite late. Indeed, while revolvers and other killing machines had become particularly efficient during the beginning of the 20th century, Kevlar bulletproof vests only appeared at the beginning of the 1970s.

Kevlar: what is it?

It is a synthetic fiber that Stephanie Kwolek created in 1965. During this time, the chemist worked for the Dupont group. To develop this material, Kwolek relied on the force that atoms could have between them. After several years of research, she developed polymers capable of resisting extreme force, thanks to this same law of physics.

How to define polymers?

Contrary to what some may think, polymers do exist in nature. It is even found in organic materials, such as wood and silk. However, polymers designed in laboratories are more like plastic. Thus, it is possible to melt them to give them a variety of shapes. Additionally, at this level, polymers become extremely resistant. Today, this material is used in a variety of industrial fields, including heavy industry.

The polymer used in bulletproof vests is Poly paraphenylene terephthalamide. It was discovered by Kwolek when she was looking to create a new plastic, so that it could be used in the process of creating new rubber for wheels. Naturally, the researcher was far from suspecting that she would soon discover Kevlar.

The secret of this material lies in its constitution. This is because the synthetic polymer is made up of a massive number of threads that are intertwined and bonded to each other, thus constituting an extremely durable fabric. Furthermore, it is resistant to cold and even extreme heat. Taking into account all these advantages, we quickly understand why manufacturers of bulletproof vests, such as DuPont, did not hesitate to include Kevlar in their jackets.

How Kevlar works

As we indicated previously, Kevlar is made up of a multitude of threads interwoven to form a fabric. Taking all its characteristics into consideration, it is not surprising that a Kevlar plate can absorb the shock of one or more bullets . To ensure that the projectile does not pierce the plate, manufacturers do not hesitate to pile several layers of Kevlar on top of each other. The more layers the plate has, the more effective it is in absorbing shock.

Of course, this also means that each layer has a well-defined boundary. This is the reason why large caliber bullets, more massive and more stealthy than others, are more likely to pierce the plates of bullet-proof vests.

Fortunately, it is possible to further protect yourself by adding steel and porcelain plates . However, you should know that these additional protections also come with more weight and are not recommended for those who need to preserve their speed and agility.

On the other hand, the fabric that covers the body armor is usually made of fibers that can become damaged over time. The good news is that it is possible to recover the plates, as long as the new protective jacket is the same size as the old one.

Since Kevlar was introduced into the manufacturing process of bulletproof vests, many lives have been saved, especially within the ranks of law enforcement . Also, in countries where the carrying of weapons is accessible to the greatest number of people, such as the United States, we can find Kevlar even in children's backpacks. These are created following a similar creation process to modern body armor. This sign, certainly alarming, is also proof of the effectiveness of Kevlar.

How to measure the effectiveness of bulletproof vests?

For decades, man was unable to effectively defend himself against gunfire. Before the invention of Kevlar, protection was rather minimal and its performance was quite poor. After several years of research and development, scientists were able to raise the level of protection to a satisfactory threshold, in particular, thanks to Kevlar. This material has unique characteristics that allow it to absorb a burst and thus prevent bullets from penetrating and then reaching the body.

Uninitiated people who purchase body armor may think that it will turn them into a veritable impenetrable fortress; a kind of human armor. However, the reality is quite different. Indeed, the absorption capacity of this protective jacket has a certain limit. This means that from a certain caliber and a certain speed of the projectile, the vest plates risk giving way and the bullet will be able to pierce the body.

Furthermore, it is important to note that in this case, the wearer risks suffering massive body damage , even before the bullet pierces the plate. This is due to the magnitude of the impact, which can cause serious injuries. Indeed, the ball can force its way partially through the plate, and it is the latter which can end up injuring you, or even causing bone fractures. For this reason, it is always advisable to opt for bulletproof vests whose plates can absorb and then disperse the shock, thus minimizing its impact on the body.

The importance of the materials used

The materials used in the manufacture of body armor are processed in such a way that they can withstand bullets from a variety of firearms. Since its creation, Kevlar has impressed experts for its capacity to absorb and dissipate energy. It is therefore not surprising that today it is an almost essential component in the manufacture of the best bulletproof vests.

Kevlar is not the only element that defines the quality of a bulletproof vest. It is also important to consider the fabric used in making the vest. Among the essential criteria to take into account are the fabric used to store the plates and the quality of the jacket straps. Indeed, these two elements can have a significant impact on the performance of the vest.

Poor quality fabric can loosen and tear at any time, which can put the wearer's life in great danger. Likewise, straps that break quickly can render the entire vest obsolete.

The strongest form of Kevlar

The strongest and most practical type of Kevlar for protective jackets is the one that most closely resembles fabric. By installing several layers, solid plates can be obtained, capable of withstanding the most stealthy gunshots. Naturally, the more layers the plate contains, the more effective it will be in absorbing shock. That said, this also means that it will be heavier. It is therefore important to choose the perfect plate thickness, depending on the need.

Also note that in this form, the fibers gain considerably in strength. So, when someone receives a bullet while wearing a Kevlar bulletproof vest, the latter will be more likely to absorb the shock, without risking injury to the wearer. Without the absorbency that this form of Kevlar provides, the risk of bullet penetration increases. For this reason, it is essential to use this type of Kevlar to protect the most sensitive areas, such as those covering the internal organs.

The size of the body armor and its impact on its performance

Many do not pay enough attention to this essential point. However, wearing the right size body armor can make a difference. Indeed, when designing a bulletproof vest, manufacturers place the plates so that they can protect the most vulnerable parts of the body. They even go so far as to carry out centimeter-level tests to find the ideal location for each protective plate.

It turns out that wearing a vest that isn't the right size can be a complete game-changer. The plates may not be located where they need to be to provide you with optimal protection , even if they end up blocking bullets. The latter can therefore be lodged in the corners of the plate, where the latter is least effective.

Furthermore, a bulletproof vest should never go lower than the level of the navel, as it can significantly limit the wearer's agility. Additionally, wearing a vest like this can also clash with stealth, as its friction with the belt and pants can make a lot of noise and alert the enemy. Finally, it is interesting to note that a vest that is worn up to the pelvis can become particularly awkward and uncomfortable when you adopt a sitting position.

What parts should the body armor cover?

As we indicated above, a bulletproof vest must primarily protect the vital organs. Therefore, it may not protect the intestines or even the kidneys, because injuries at this level are not fatal. That said, from a purely technical standpoint, you can cover the vast majority of your body if you want. Of course, this will come at the expensive cost of your mobility and stealth. Indeed, by covering your body with all possible plaques, you will barely be able to move.

As you can see after reading this article, the proper functioning of a bulletproof vest essentially depends on the quality of its manufacturing. If it's poor quality, even a Kevlar body armor can put you at far more risk than you think. That said, now that you know more about how body armor works, you will certainly be better able to choose the one that will be most useful to you. Remember to base your choice on your needs, as better protection isn't always what you're looking for in a new vest.

Find now on our Delta Tactical site many models of bulletproof vests , such as NIJ 4 Bulletproof Vests . You will also find other varieties of protective jackets, such as a Security Guard Bulletproof Vest .

Up to you !