We have never seen the cap strip the threads from the steel die body. The die body is hardened steel. The cap is soft aluminum. We use the aluminum cap as a safety valve to prevent damage to the steel die parts. The stripped threads from the cap are just lodged in the die threads. Most often the aluminum comes out of the steel threads in one continuous coil once you begin to remove it. If you take a shop rag and stuff it very tightly into the top of the die and "unscrew" the rag out of the die, the stripped threads will follow. Any bits and pieces left in the threads can be removed with a stiff wire brush.
We have a built in stop on our presses which eliminates this excessive power curve at the top of the stroke. We use the aluminum Cap as a weak link. Otherwise the Collet in the Die would be destroyed.
Per the Instructions, screw the collet neck sizing die in until it contacts the shell holder, plus one more turn (1 3/4 turns for Lee Classic Series presses). If you are following these instructions and have still stripped your Cap, you have a couple of options to prevent this: Add another 1 turn to the die depth, and or do not put so much pressure on the handle.
If you are using the Collet die in an RCBS Rockchucker press, or a similar design that toggles over center at the top of the (ram) stroke, this applies far greater force than is necessary to resize just the neck of the case and can damage the die or collapse the case. To correct this situation, adjust the die two full turns into the press after the die contacts the shell holder with the ram at the top of its stroke, rather than one as in the instructions. If you are using a Lee Precision "Classic" series press, adjust the die 1 3/4 turns into the press. This will stop the press before it gets to the toggle over point. With a press without having an over center feature, apply about 25 lbs. of pressure to the handle once it bottoms out to resize the case. On most presses, this translates to over 600 lbs of pressure on the ram.
Special note for Forster Co-Ax Presses: You would adjust the die the same 2 full turns past firm contact with the shellholder as you would above. However, the difference is that only 15 to 20 pounds of pressure is needed to be applied to the press lever on a Co-Ax. If you have another single stage press, we suggest that you use that instead. The Co-Ax is generally just too powerful for the 7/8"-14 Collet Neck Sizing Die.
