Abstract: A firearm sighting aid device for making it easier and quicker to adjust the sights of a firearm. The firearm sighting aid device includes a housing having an open front end, an open back end, and a compartment disposed therein with the housing being adapted to be received in a chamber of a firearm; and also includes an endcap member being removably attached to the back end of the housing to essentially close the back end of the housing and to close access to the compartment; and further includes a light-emitting member securely disposed in the compartment near the front end of the housing and being adapted to emit a beam of light through the open front end of the housing and through a bore and out of a barrel of the firearm; and also includes energizing assembly for energizing the light-emitting member.