I recently acquired one of the Sinclair caseholders and wish I woukld have found them years ago. I have used the Lee caseholders for years and even purchased the universal caseholder (with the 3 jaws) and none of them come close to the Sinclair. The cases stay tight with minimal force tightening the holder, and I didn't have a single case come loose like I got used to with the Lee. Also the long Hex shaft stays in the chuck of a cordless screwdriver.
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SINCLAIR INTERNATIONAL NECK TURNING CASEHOLDERS | Brownells
The Sinclair Driver and Caseholder system is designed to hold and turn your case while you are neck turning, cleaning case necks or case mouth deburring. The caseholders and driver are machined from stainless steel, and the driver has a ¼" hex sha...