The 9mm is one of the most difficult cases to size. The reason for this is that the case is tapered and as a result more of the case is in contact with the carbide ring, increasing the friction. A couple of tricks can make the resizing job easier.
Do not clean your cases before sizing. Clean shiny brass is the most difficult to size. Clean brass tends to be sticky and can gall your die. The oxides and graphite that build up on fired cases make them slippery and easier to size. If you do clean your cases before sizing use a spray lube or even a light spray of aerosol furniture polish. Another trick is to put your cleaned cases in a lightly oiled cloth and massage them between your hands like a bag of marbles to give them a light coating of oil. Doing any of these things will make the resizing job a lot easier and eliminate stuck cases.
If you have sized a lot of cleaned cases without lubing them you may have some brass buildup (galling) on the carbide ring. You can remove this by wrapping 180 grain emery paper around a dowel and sanding the carbide ring. The emery paper will not scratch the carbide.
