The Forster Outside Neck Turner Accessory for Original Case Trimmer is unique because rather than being centered on the pilot only as with handheld turners the case is turned concentric to true axis. With this turner neck walls are made of uniform thickness as well as the same outside diameter.

When adjusted properly this turner reaches a tolerance of 0.0001 inches. In addition the cutter head is designed with a circular carbide cutter that can easily be adjusted. The feed rate is controllable simply by rotating the feeder cam while the length of the cut is controlled with a mechanical stop.