Set consists of a full length resizing die with decapping stem and neck expanding button and a bullet seating die. In addition, Lyman has included a neck sizing die with a carbide expander. This extra die enables the reloader to extend case life by reducing the amount of stretching caused by excessive sizing. These die sets are the reloader"s best choice for loading jacketed bullets in bottlenecked rifle cases. Standard 7/8 x 14 thread. The best choice for loading 223 Remington (5.56mm) cartridges.