#firearm__piece__small-arm__smallarm  a portable gun; "he wore his firearm in a shoulder holster"
  supertype:  gun  a weapon that discharges a missile at high velocity (especially from a metal tube or barrel)
  subtype:  autoloader  machine_gun  muzzle_loader  pistol  repeating_firearm  rifle  shotgun  .22
  part:  firing_pin  striker that ignites the charge by striking the primer
  part:  lock.mechanism  a mechanism that detonates the charge of a gun
  part:  sight.optical_instrument  a optical instrument for aiding the eye in aiming, as on a firearm or surveying instrument
     part:  eyepiece__ocular  combination of lenses at the viewing end of optical instruments
        part:  reticle__graticule  a network of fine lines, dots, cross hairs, or wires in the focal plane of the eyepiece of an optical instrument
           part:  cross_hair__crosshair__cross_wire__crosswire  either of two fine mutually perpendicular lines that cross in the focus plane of an optical instrument and are use for sighting or calibration; "he had the target in his cross hairs"

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