I too use the ram to square the nut when starting it. My 450 must seal at the die bottom well because I shot a bullet through it yesterday and it came out completely lubed too! It has been setting a week or more and still had some pressure on the lube. I only "snug" the nut as it looks frail to me. My sizer had a problem with the lube leaking under it. After replacing the o ring and cleaning and fussing I realised that it had been machined at an angle to the bore(not 90 degrees). It had bent the pressure screw frome being off too. I epoxied the plate on the bottom of reservoir in and lapped the seat on the screw straight and it works great now. They are still way too wimpy for the job IMO. Jay