A needleless injector has a syringe body having an opening at one end, a piston housed within the syringe body for urging a liquid within the syringe body through the opening and a ram for driving the piston. A shock absorbing component is provided for reducing an initial transfer of force from the ram to the piston. The initial rate of pressure increase on the liquid is reduced, thereby controlling the rate of collapse of gas bubbles in the liquid.