Originally Posted By: ackleymanCam over on full length sizing is required on many guns, especially customs with minimimal headspace.
When you set your die in the press, be sure to do it while sizing brass. When you screw down the die to touch the shell holder, then size a piece of brass, you will find that the die is no longer touching the shell holder.
Another term I've never heard of, but have been practicing. By trial an error, I found using this method for my T/C rifle barrel was the way to go. It cured my headspace issue.