The Lyman Standard Rifle Neck Sizer Die allows the reloader to properly size the case neck for optimal bullet tension while maintaining the fire-formed dimension of the case body. Accuracy is increased when the case body closely fits into the chamber. The Neck Size Die includes a decapping rod and steel expander button. Improve the accuracy of your standard rifle such as the 204 Ruger with Lyman?s Rifle Neck Sizer Die.