A power injector syringe assembly (100) that includes a syringe body (110) having a syringe barrel (120). An outer wall (126b) of the syringe barrel (120) is tapered from its proximal end (122) to its distal end (124), with the outer diameter of the syringe barrel (120) progressively increasing when proceeding in the direction of its distal end (124). When this syringe barrel (120) is disposed within a pressure sleeve (180), the clearance between the outer diameter of the syringe barrel (120) and the inner diameter of the pressure sleeve (180) is progressively reduced proceeding in the discharge direction during power injector operations.
