The Redding Neck Sizing Dies are designed to size only the necks of your bottleneck cases, a process that helps extend brass life and enhances accuracy. Since these dies do not resize the shoulder or body, it's important to never interchange fired cases between rifles. These dies are perfect for cartridges used in bolt-action rifles, where precision is critical. Manufactured from the highest-quality alloy steels and machined on Hardinge Super-Precision lathes, these dies are engineered to maintain the tightest tolerances in the industry. Each die is heat-treated in atmospherically controlled furnaces and hand-polished for smooth, flawless operation. With their superior construction, these dies are built to last a lifetime while maintaining their precision. Before packaging, each die is thoroughly inspected and ultrasonically cleaned, ensuring the highest level of quality and performance.