Who makes a good 5C Collet ? I've wasted money on collets that were smaller than they should be and I end up with parts getting stuck. I've also have found that some collets have a thread relief on the O.D. so large that the key in my index head will find its way into this groove causing me much grief.

Hardinge makes the best collets I have ever used in the past twenty years. We by them through DoAll company (DGI) run about 25-30 dollars. I two have run across the same promblems with the cheaper collots not opening or being to soft even.
Good luck
John