The Forster Hand Held Outside Neck Turner tool allows the reloader to make absolutely certain that their bullet is being released consistently from the case neck. At the point of ignition, the case neck must expand to allow bullet release. If the case neck is thicker on one side than the other, the thinner side will release the bullet sooner and causes a slight bullet-to-bore misalignment that can seriously impair accuracy. These steel pilots, also called mandrels, are precision ground .002" to .0025" smaller than bullet diameter for optimum performance.