Re: Newbie reloading question about die adjusting
The part that you referenced is the decapping/expander.
Before you use the die, I would take it apart and polish the expander and the inside of the die using Flitz metal polish. I do this with all my die, but the Lee die need it especially. You don't want to take any metal off, just smooth everything up.
Also, be careful setting the sizing down too far, you could work the brass too much pushing the shoulder back needlessly. I suggest you get, Handloading for Competition by Glenn Zediker. It is an excellent read and will help with a lot of your questions and help make the best of your handloads.
"One of the ordinary modes, by which tyrants accomplish their purposes without resistance, is, by disarming the people, and making it an offense to keep arms."
-- Constitutional scholar and Supreme Court Justice Joseph Story, 1840