this might be a dumb question.....but how do you know if the expander ball in the die needs to be replaced? is it visually damaged or what. i ask this question because i just removed a stuck case from my die. it seems to be fine to me. thanks

If possible you might polish it with a little metal polish like flitz. If you can't see an imperfection and don't feel any "catches" when spinning against a rag it should be fine. You could also roll the whole spindle accross a table and look for a wobble...if you can't see one we'll assume you didn't hurt the spindle.

Your stuck case was no doubt from not enough lube in the die when sizing?

As long as you have the die apart I'll list how I put them back together and adjust for low runnout....below....it works great in most any die....

ALL dies with expander balls need tuning. Think about it...a piece of typing paper is .003" thick--what are the odds that the expander is not PERFECTLY centered in a die and could pull a case slightly off center??? Pretty good I'd say. Pull the expander stem out of the die (and now is a good time to clean the inside of the die). Run about 5 brass into the die and see if they come out concentric. If they do (and usually they will) you now have to try and get that stem centered on re-assembly. A great way that helps is to put a piece of very concentric brass up into the die to hold the stem in place as you tighten it down. Sometimes this takes 2 people unless you have 3 or 4 hands. AFter reassembly try sizing some brass and check runnout. If not good then do very small turns of the expander stem--probably 1/32 of a turn at a time. Resize some brass and repeat the small turns. At some point I can almost guarantee that you will get GREAT RUNNOUT CONSISTANTLY. (Somehow, someway the expander spindle will hit almost perfect centering in the die body) I have many dies that consistantly make less than .002" runnout after sizing with most of the brass at .001" and less. I own, hornady, redding, forester, rcbs, and lee dies. ALL OF THEM HAVE BEEN TUNED and most make fantastic ammo and all make good ammo!! I have never ever got a set of dies from any factory that made as good of ammo as those that I have done this simple work with.

If it's not badly scratched or galled up it's probably fine. Polish it with some 600 grit paper and you'll be more than likely good to go. You'll probably notice a smoother sizing operation too. I polish all expander balls, even with a brand new die.