A laser bore sight (10) is disclosed hollow, outer housing (11) having an internally threaded, rear portion (14), and a threaded end cap (17) is sized and shaped to be threaded to the housing rear portion (14). The end cap (17) includes a threaded, tubular stem (18) having an annular rim (18'), an electrically insulative spacer (20) and a spring (21). The bore sight (10) also includes a laser diode (24), lens (25), a series of three batteries (26), an electrically conductive spring (27), and an electrical conductor. The end cap (17) is movable between an extended position with the spacer protruding from the end of the stem (18) and a retracted position with the spacer recessed within the stem so as to allow the battery to electrically contact the end cap.