A piston for a pressure-reducing valve includes a tubular housing having an internal longitudinal bore extending from a first end to a second end. An exterior circumferential sealing disc sealing engages internal walls. The sealing disc has upper and lower faces generally perpendicular to a longitudinal axis. First fluid port(s) and second fluid port(s) extend through the tubular housing and into the longitudinal bore. A piston stem sealingly engages an internal surface of the longitudinal bore between the sealing disc and the second end to prevent the passage of fluid. The piston stem, together with a portion of the longitudinal bore, forms fluid passageway(s) that fluidly connect the first fluid port(s) with the second fluid port(s). The second fluid port(s) are inclined relative to the longitudinal axis and extend through at least a portion of the sealing disc, intersecting at least a portion of the upper face thereof.