Abstract: A pneumatic outlet gate of a railroad hopper car has an valve member mounted for rotation in a discharge tube between open and closed positions. The valve member is an arcuate segment terminating laterally at edge faces. The edge faces are angled such that in the upper half of the discharge tube they always slant downwardly from the surface of the tube, while in the lower half of the discharge tube the edge faces face downwardly. An arrangement of stops and abutments prevents rotation of the valve member to a location where the edge faces could trap lading against the discharge tube. Accordingly, the edge faces are self-emptying.