Owing to their high productivity, pressure invariance, and controlled throughput and melt temperature, groove feed systems are becoming widely accepted for the extrusion of pipes, blown films, and blow molded articles. Within the research presented in this paper, a fully instrumented 45 mm extruder equipped with a grooved fed bushing was used to measure pressure distributions, screw and die characteristics, and melt temperature profiles. The screw geometry included decompression and compression zones, and Saxton distributive and Maillefer dispersive mixing heads. The screw and die characteristic curves show the high system productivity where throughputs comparable to 60 and 90 mm conventional extruders were measured. The high throughput induced a dramatic reduction in melt temperature measured at the tip. To better understand and confirm our experimental findings, analytical models were used.