Originally Posted by
45_Colt
As you get close to where you want/need to lock the lock into position. Tighten the lock ring screw as much as possible and still be able to _just_ adjust the die. Then back off the ring a smidgen and lock it into place.
Double check the adjustment and go from there.
The issue is that split rings close into the threads, which usually cams the ring further downward. This is due to the ring riding higher on the threads when loose. Then as the ring is tightened it moves with the direction of looseness in the thread.
Which is typically down, this is what locks the die up tight.
45_Colt
P.S. re-reading this looks confusing, hope it helps...