A powder burn is a type of burn caused by exposure to the burning gases which are expelled from the muzzle of a firearm as it is fired. Powder burns only occur when the person or item to be burned is close to the discharging firearm, as the gases quickly dissipate. This can be an indicator on a corpse of whether the person was shot at point-blank range or not.
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Powder burn Wikipedia(Text) CC BY-SA