How Hard Body Armor Works

Level III body armor is type of hard body armor.  Hard body armor is used in a tactical situation to give the wearer extra protection against both high speed pistol caliber ammunition, and rifle caliber ammunition. Hard body armor is generally a rectangular plate of material, either ballistic ceramic or ballistic steel. Each material has their strengths and weaknesses. Ceramic plates are usually thicker but lighter than a steel plate of the same protection. Steel plates can take more hits than ceramic plates, but ceramic plates are more likely to trap the bullet, keeping it from becoming a richochet that could endanger fellow teammates or innocent bystanders. Ceramic plates are more expensive than steel plates and may shatter if they are dropped. Steel plates require a lining on the rear of the plate to prevent shards of the metal from fragmenting off the plate and into the wearer, an effect known as 'spalling'.

Hard armor is worn usually in conjunction with soft body armor. The hard armor takes the initial impact, and, depending on the type of ammunition that hits it, deforms a bit in the back, and the Kevlar takes the rest of the impact.

A person wearing body armor will still feel the energy of a bullet's impact, of course, but over the whole torso rather than in a specific area. If everything works correctly, the victim won't be seriously hurt.

Since no one layer can move a good distance, the vest, example the level III body armor has to slow the bullet down using many different layers. Each "net" slows the bullet a little bit more, until the bullet finally stops. The material also causes the bullet to deform at the point of the impact. Essentially, the bullet spreads out at the tip, in the same way a piece of clay spreads out if you throw it against a wall. This process, which further reduces the energy of the bullet, is called "mushrooming."