An applicator instrument for dispensing surgical fasteners comprising: a housing having a cartridge opening, an elongated shaft extending from said housing , a handle coupled with a proximal end of said housing, a trigger coupled with said handle , a firing system including an energy storing assembly disposed within said housing, and a gear train disposed within said handle and coupled with said trigger ; a first cartridge containing first surgical fasteners configured to be inserted into said cartridge opening; wherein when said first cartridge is inserted into said cartridge opening, said trigger is squeezable and configured to store energy in said energy storing assembly of said firing system and then release the stored energy to remove one of said first surgical fasteners from said first cartridge , advance said removed first surgical fastener from said housing to said elongated shaft , and dispense said removed first surgical fastener from a distal end of said elongated shaft ; a second cartridge containing second surgical fasteners configured to be inserted into said cartridge opening when said first cartridge is removed from said cartridge opening; wherein when said second cartridge is inserted into said cartridge opening said trigger is squeezable and configured to store energy in said energy storing assembly of said firing system and then release the stored energy to remove one of said second surgical fasteners from said second cartridge, advance said removed second surgical fastener from said housing to said elongated shaft , and dispense said removed second surgical fastener from said distal end of said elongated shaft . a housing having a cartridge opening, an elongated shaft extending from said housing , a handle coupled with a proximal end of said housing, a trigger coupled with said handle , a firing system including an energy storing assembly disposed within said housing, and a gear train disposed within said handle and coupled with said trigger ; a first cartridge containing first surgical fasteners configured to be inserted into said cartridge opening; wherein when said first cartridge is inserted into said cartridge opening, said trigger is squeezable and configured to store energy in said energy storing assembly of said firing system and then release the stored energy to remove one of said first surgical fasteners from said first cartridge , advance said removed first surgical fastener from said housing to said elongated shaft , and dispense said removed first surgical fastener from a distal end of said elongated shaft ; a second cartridge containing second surgical fasteners configured to be inserted into said cartridge opening when said first cartridge is removed from said cartridge opening; wherein when said second cartridge is inserted into said cartridge opening said trigger is squeezable and configured to store energy in said energy storing assembly of said firing system and then release the stored energy to remove one of said second surgical fasteners from said second cartridge, advance said removed second surgical fastener from said housing to said elongated shaft , and dispense said removed second surgical fastener from said distal end of said elongated shaft . <EOS>