Sniper-proof: .50 Caliber Bullets Can Kill. Meet the Body Armor That Can Stop Them
How effective is it?
Heavy machine guns and sniper rifles in .50 caliber are some of the most feared weapons for the infantryman on the battlefield. As the .50 caliber round was originally meant to pierce armor and take down aircraft, a hit is practically guaranteed to incapacitate a soldier. Most body armor is useless against .50 caliber rounds, as they are only meant to protect against cartridges with less than 1/3 of the energy of the .50 caliber.
But some special body armor exists that protects against .50 caliber projectiles. These plates are only issued to aircrew, as their immense bulk and weight severely limit the mobility of a soldier. The plates were also usually limited to covering the front of an aircrewman, as the rear and sides were assumed to be protected by the armor plating of an aircraft. But as .50 caliber guns are commonly used in the anti-air role, protection against the caliber was deemed important enough to develop body armor to counter it.
Aircrew have a history of being some of the first to receive body armor technology due to the relatively stationary nature of their work. During WWII, U.S. Army Air Forces bomber crewmen wore ballistic nylon and steel flak jackets to protect against shrapnel from shells. Two models were produced, one with full coverage for gunners who would have to stand, and one with just frontal coverage for pilots who would have an armored seat protecting their back. This pattern of producing multiple kinds of vests for aircrew would be repeated later in history.
However, WWII flak jackets only protected against shrapnel and pistol rounds, which were relatively low velocity. They would be pierced easily by regular machine gun rounds.
This level of protection was not enough for helicopter crewmen during the Vietnam War, who began the war wearing vests of WWII and Korean War vintage. New vests were needed for helicopter crewmen, who often were faced with machine gun fire from various 7.62×39 and 7.62x54R (.30 caliber) weapons on the ground.
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