Thread: lee collet die issues

Last weekend I bought a lee collet die for 303. Tested it it out on a few case and couldn't get the inside neck diameter small than .309 of a inch, I can push the bullet in by hand. My old lee loader and lee FL die gets the neck down to .305 which to me is perfect for optimal neck tension. After some research found out that people with the same issue sand down the mandrel a few .001's of a inch to achieve better neck tension, so I tried it and got the mandrel from .307 to .305. tested a couple of cases and still was getting .309 inside diameter, had to turn the cases in the shell and resize several times and apply at least 35 ft-lb of pressure (used a torque wrench with attachment) to get between .305 to .307. Doesn't seem right because my 243 collet doesn't require anywhere that much work to achieve optimal neck tension. Am I missing something, am I doing something wrong, has anyone else had this much trouble with a collet die?