In reality, the probability of a bullet directly hitting the human body at a short distance is very small, and the human body needs to bear more fragments produced by explosives such as shells, bombs, hand grenades, and long-distance firing of light weapons.Taking World War II as an example, I have seen a data analysis before that the number of people killed by gunfire in the war is much higher than that directly killed and killed by bullets.At present, the bulletproof vests can effectively resist the impact of various fragments and stray bullets. At the same time, the bulletproof vests can also effectively disperse the impact of air waves generated by explosion on human organs.This is the fundamental reason why soldiers equip and use bulletproof vests.
Similarly, up to now, there is no helmet in the world that can withstand the direct hit of standard rifle bullets within 100 meters.Take the type 56 submachine gun (AK47 made by the Soviet Union) which was widely equipped and used in China for example, the gun can effectively penetrate 6 mm homogeneous steel plate at 100 distance by using ordinary walking machine projectile. However, the thickness of the thick part of the helmet used in China is only 3 mm, that is to say, even if two helmets are worn, it is difficult to resist the direct hit of AK47 at close range,So why are countries all over the world equipped with heavy helmets?The reason is that the purpose of wearing helmets is not to prevent bullets from hitting directly, but to kill them by bullet proof pieces and stray bullets. The probability of soldiers being hit by shrapnel and stray bullets in combat is much higher than that of soldiers directly hit by bullets.Therefore, whether wearing a helmet or a bulletproof vest can effectively reduce casualties.