Hi, You don't mention which Lee Turret you are using. I encountered sonething similar on the old Lee 3 station turret , but the problem was with all the cases in all calibers; it was due to that weird little primer arm being a bit too shorter at the bottom due to wear. Once replaced the problem went away. If you are using their newer classic cast turret press with 4 stations the priming arm is stronger and gets more push from the larger ram and more mechanical advantage is involved. If some primers are being seated correctly without cratering or curling the edges and to the proper depth then all primers should be seated/seating without a problem. Something is interfering with the primers seating fully. Even before lookimg at some possible defect in the primer arm itself I would check out A) the shellholder for any dirt, speck of brass or other something that may be causing the rim of the cases/some cases to tilt or not go all the way into the SH. it happens and SH's have to be checked often and kept clean. B) Double check all of your brass' primer pockets and make sure that they are clean. Residue builds up even with one firing. A small 1/8" screwdriver can do the job or else you can make a very good primer pocket cleaner out of a piece of old hacksaw blade which is very hard steel. You just grind one end to a cone shape and then cut the end off and grind it a little on each side until it ressembles a screwdriver blade tip that fits the diameter of the primer pocket...one end of the hacksaw blade for large and the other for small. It'll last forever and does a good job of cleaning the pockets. If A& B above don't solve the prob then there may be something wrong with the primer arm; what exactly I don't know as there isn't much to a primer arm, but its a machine part and sometimes it can have something wrong somehow. If that is the case then I would suggest sending it back to Lee with an explanation, or call them; they are pretty good about following up on stuff like that. Another thing to check altho the possibility is remote is the uniformity of the primer pockets themselves; it s sometimes an issue. Hope that some or any of this works for you as you have a good press there. JC