I have been reloading for about 2yrs now with my Dillon xl650, I run the sizing die down until it touch’s the Shell plate & then back it off 1/8-1/4 turn. On crimping, I crimp my loads .001-.003in basically enough to take the bell off plus a little. I do this on all my straight case loads (.45acp, 9mm, .38spcl/.357 & 45-70) ,fairly important on any revolver loads.
also I check the COL on every round as well as run everyone through a chamber gage to make sure they fully seat. It’s a “must do” for me To control the quality of my loads.
i also have 2 old single stages that I use for reworking any non-conformance, one is equipped with a sizing die and the other has a seating/crimping die. I can’t say that in all the loading write ups that I’ve read that any of them have recommended not crimping of some kind particularly with belling the brass. The G.FL. brass may be slightly longer than your other brass which would make the bell bigger, wouldn’t have to be much. My .02