One aspect relates to a bone cement applicator having a cartridge with an interior, a cartridge head with a delivery opening, a mixing member which is movable in the interior with a mixing rod. A delivery plunger is arranged in the cartridge and is mounted in the interior and is pressable in the direction of the delivery opening. The delivery plunger rests with an outer cylindrical circumferential surface against an inner wall of the cartridge. A clamping element is arranged on the inner wall of the cartridge in the region of a back side of the interior. The clamping element projects out of the inner wall of the cartridge. The cylindrical circumferential surface of the delivery plunger is resiliently deformable by the clamping element in the direction of a central cylinder axis, such that the delivery plunger is clampable in place with the at least one clamping element on the back side of the cartridge.