Hornady Mandrel Loader .243 .2395 5053. The case neck turning tool is just the tool you need to quickly and accurately trim the outside of your case necks to reliable uniformity and the mandrel comes in several different sizes to accommodate different calibers. When using the Hornady Case Neck Turning Tool you need a caliber-specific mandrel to ensure proper alignment when turning down the case neck size. That is where the Hornady Neck Turning Tool Mandrel comes in. This tool is available in .22 .30 .and .243-caliber sizes. Specifications for Hornady Neck Turn Tool Mandrels: Manufacturer: Hornady Quantity: 1 Finish: Silver Package Contents: Hornady Mandrel Loader Hornady 5053: Mandrel Loader .243 .2395