With some pistol dies it feels like the expander is sticking in the case mouth. It feels like that because as the case is being extracted from the die, the expander stays with the case for some of the downward travel, then the expander hits an internal shoulder, stops, and the case is pulled off.
What you can do to soften this release is to polish the small diameter of the expander sleeve, and apply some LEE Resizing Lube to it. This will allow it to release easier.
The amount of flare to the case mouth is relative to how deep you screw the die in to the press. It flares the most just before the case hits the shoulder on the expander sleeve.
