Over flaring with the Lee powder through expander in 45 ACP can cause brass to shave. The BASIC adjustment for the die is one turn backed off from shell holder contact with the ram full up...NOTE that closer than the one turn back-off setting to the shell holder INCREASES flair and farther than the one turn decreases flair.
The goal in setting the adjustment of the Powder Through Expander die is to use the least amount of flair that allows easy bullet seating without shaving the bullets. Without experience it is a guess how much flair is needed. The die has a wide range of adjustability and can certainly be over adjusted in either direction from the BASIC setting.
This is helpful: after sizing a 45ACP case remove it from the shell holder and measure the case mouth diameter with a micrometer. Record the measurement. Now adjust your powder through expander to flair the case mouth .003" larger than your recorded sized case mouth diameter.
Try some loading and observe if your bullets seat easily and if they are leaving any lead shavings from cast bullets.
If you are shaving lead increase flair an additional .001 to .002". Or if the seating starts with a bump because bullets are catching you also need more flair.
You should NEVER need more than .004" flair to seat cast bullets and if you do something else is wrong. It is not the die setting and likely your bullet diameter or out of specification brass wall thickness.
Also, brass trim to length isn't often needed for 45ACP but if you trim and leave the edge sharp, your expander will not like that. After trimming, at least break the sharp edge with a chamfer or your expander may collapse a sharp trimmer flash of brass or cut it off and make it look like a shaving.