Efficient screw design requires a good geometric design of the outlet/feeder combination in order for the bulk solids to be entrained over the full length of the outlet. This is essential to control the feed from mass-flow bins with wedge or transition shaped hoppers to achieve an even flow pattern in the bin or hopper. This paper reports experimental studies on the flow pattern in a wedge hopper with a single screw feeder. Two screws of different configuration (both having an increase of the screw capacity in the flow direction) and two types of bulk solids were investigated on a test rig. Some theories for achieving a uniform draw-down performance are discussed and requirements for hopper geometry are proposed.