1. The problem statement, all variables and given/known data I don't know if this one belongs to something like the mythbusters, because of the complexity it needs for the actual testing. This is the situation: in my country every week somebody gets hurt because of stray bullets, This is provoked by irresponsible people who tend to celebrate by firing guns into the air as if they don't realize that the bullets eventually come back down. Usually the injuries occur when the bullets go true metal roofing and/or wood roofing. The metal roofing material used in third world counties is usually corrugated galvanized tin leafs 2 meters long by 1 meter wide. 0.2 cm thick. the wood is usually 0.5' pine plywood (the one you USA's use for hurricane protection). The question here is what would be the final velocity of a 45 caliber bullet (most commonly used caliber in my country) fired from a (taurus, baretta) type hand gun. And if possible what would be the impact force at final velocity. Let's say that the gun is fired at 90 degrees, 80, degrees, 75, degrees, and so on. 2. Relevant equations the bullet waight is important and imagine a wind speed of maybe 10 m/h for the present wind. 3. The attempt at a solution The answer to this problem might give us an idea on how many sheets of metal would be needed to prevent a stray bullet from going true and hurting people. thanks.