A laser bore sight with arbor system is disclosed which includes a bore sight with a housing, a laser and an activation switch. The system also includes a plurality of arbors, each arbor having a sleeve with an interior channel configured to be received the bore sight. Each arbor is configured to fit within the bore and/or breach of a firearm. The exterior configuration of each arbor is different and specifically configured to fit a specific caliber of firearm. The sleeve has a rear end to which is coupled an end cap having and opening through which the bore sight activation switch extends.