An applicator 102 has a fluid supply inlet (14), an outlet (4) and a barrel (1) having a barrel outlet (2) and a barrel inlet (15a). The barrel inlet (15) is in fluid communication, or selective fluid communication, with the fluid supply inlet (14). A one way outlet valve (3) is in fluid communication with the barrel outlet (2) and with the outlet (4). The applicator 100 has piston actuation means (32) for moving a piston (5) relative to the barrel (1). The applicator further comprises pressure limiting means (10) for limiting a maximum pressure of fluid entering the barrel (1) from the fluid supply inlet (14).