Lee Collet Neck Sizing Die Techincal Support - Squeezing The Case

Author: Lee Product Team  

What to do if the Lee Collet Die has crushed or Squeezed your case?

All of the sizing in the Lee Collet die takes place at the very end of the stroke, when the ram/shell holder appears to bottom out against the base of the die. If you lean into the handle at this point, you will force the collet up into the die body, and cause the collet to squeeze the case neck down against the mandrel (the very end of which pops out the spent primer). About 25 lbs. of force is sufficient to resize most cases. If you are sitting in front of your press, just leaning your upper body weight into the lever is about right.

A good way to determine how much is necessary is to start the case into the die and feel the die remove the primer. Start using pressure and work up to what you think is about 25 lbs. Remove the case from the die and attempt to place the intended bullet in the case neck. If there is little or no resistance, repeat the process with slightly more pressure. When you have reached a point where there are vertical striation marks on the outside of the case neck or the intended bullet does not fit easily into the case neck, the correct amount of pressure has been achieved.

What to do if the Collet Die has crushed or Squeezed a few cases? On inspection, the neck of the case doesn't fit into the Collet Die neck as the Collet Die neck is too small for the case neck?

Firstly, check to make sure you have the right Collet Die for the case you are trying to resize.  Accidents do happen! Then, What brand of press are you using the collet die in? If the press will cam over then the die must be installed 2 full turns past firm contact with the bottom of the die. This installation will keep the press from camming over on the die.

If the press does cam over on the Lee collet die the eventual result may be that the collet will become collapsed. When this occurs the small hole formed by the four collet fingers will have become too small for the fired diameter of the case neck to enter. Then the case mouth catches on the under side of the collet fingers and is crushed. Luckily the Lee Collet is easily repaired.

Here's how.

You will need a medium size phillips head screw driver. It must have a round shank. Slide the bottom end of the collet into the bottom end of the threaded die body. This will provide for a larger handle to hang onto. Now slide the tip of the screwdriver into the small hole formed by the collet fingers and slowly with a controlled amount of pressure not to break the finger, pry each collet finger back about 1/16". Do not worry about getting the fingers exactly even. The die body and sleeve will align the fingers in the die. Check to make sure that the fired case neck fits freely in the hole formed by the collet fingers. It should be able to wiggle side to side in the hole. Lubricate and reassemble the die.

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