Thread: Can The Lee FL Die Do A Shoulder Bump?

Originally Posted by Rn-85

I think I'll go to that method after all I really like using my lee loader.

Is the correct process to trim before fl resize?

Sorry for the newbie questions.

Its a good question and Dicko is correct. Folk do seem to confuse it tho. Just remember the case is length stretched in two actions. First is when you fire the round and the case expands to the form of the chamber which is always larger and longer to allow the round to be chambered. Second is when the case is sized forcing it back to original dimensions. Both instances cause the case to lengthen. The brass walls thin a tad under firing pressure and sizing. The brass has to go somewhere and it flows into extra length. You can test this by trimming to length say 50 cases before FL sizing. Then gauge again. A few will require retrimming. It won't be consistent because cases still vary in wall thickness in the body. And it will be a very marginal amount. Nevertheless it is enough to affect accuracy to some degree. In very tight chambers it may cause difficulty closing the bolt. In a tolerant chamber it probably makes little difference for hunting.