The Hornady Powder Cop Die is the perfect for your progressive reloading press. Just install the die after the powder drop station to automatically check dropped charges. The powder cop die has an internal stem that will move up to display a white o-ring that is even with the surface of the die when the correct powder charge is in the case, when the die is properly set. If there is no powder charge in the case the stem will not rise. If there is an overcharge of powder, the stem will lift the O-ring well above the surface of the powder cop die allowing you to easily see the case is over-charged. Works with 22 Cal. and larger cartridges.