A firearm (10), in particular a repeating shotgun, comprises a stock (11), a barrel (30) which is supported in axially displaceable manner relative to said stock (11) at or in a linear guide (20), a cartridge seat (31) to receive a cartridge (P) being configured in said barrel (30), further a closing system (40) fitted with a closing head (41) to close the cartridge seat (31), said closing head (41) being axially affixable in place in the barrel end (32, 33) when the firearm (10) is being closed and being traversed centrally to the barrel axis (A) by a striker pin (18), and a locking system (80) to lock the firearm (10) in its closed position. The closing system (40) is substantially configured axially symmetrically and/or rotationally symmetrically to the barrel axis (A).