"A firearm is a gun (a barreled ranged weapon) designed to be readily carried and used by a single individual. It inflicts damage on targets by launching one or more projectiles driven by rapidly expanding high-pressure gas produced by exothermic combustion (deflagration) of chemical propellant. If gas pressurization is achieved through mechanical gas compression rather than through chemical propellant combustion, then the gun is technically an air gun, not a firearm. Some legal definitions of "firearm" are more broad, and may cover any and all projectile devices, or even other destructive devices." - (en.wikipedia.org 01.03.2020)
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