The RCBS X Die Full Length Sizer Only offers excellence for people who do reloading. This individual die is made from steel; for reloading ammunition used in pump slide automatic semiautomatic and a few rifles with lever action this is an excellent choice.The sizer die sizes the body of the case a little smaller in diameter compared to that of a standard die and boasts a special mandrel design. After making a first trim of 0.02 inches no additional trimming is required and the neck wall does not thicken as the length of the case is pushed back.