The answer to the question depends on what level of threat the
armor needs to stop. As we discussed in a recent post, the
Kinetic energy of a bullet can be calculated if the weight of
the bullet and the speed of the bullet are known using the
following formula: Kinetic Energy (Joules) = 1/2 x Mass of
bullet (grams) x [Velocity of bullet (m/s)]^2 The more Kinetic
Energy the bullet has, the thicker and heavier the transparent
armor needs to be. Of course there are many manufacturers of
bullet resistant glass and transparent armor. Each of these
manufacturers have their own knowledge of how to produce the
lightest and thinest armor to stop a specific threat. However,
if we look at the top military transparent armor producers,
there is only limited variation in the performance of the
products. We recently compared data published on the internet
from the top laminators to see how thick and how heavy their
products are to stop a given threat. We compared products that
were designed to stop rounds with between 650 J