Wet tumbling leaves the cases dry & oil-free. Even when nicely polished, these cases can require much greater force to resize (w/carbide sizer) than say dirt free, but tarnished, cases.
Try the Star recommended lanolin trick on 15 or 20 cases and see if that doesn't clear up the issue.
From page 4 or the Star instruction booklet:
DO NOT use gasoline or solvent on your shells. It makes them so dry that they may stick to
the die and cause scratches. After your shells are clean and free of grit just before starting to
reload, dip the tips of your fingers in hydrous lanolin and stir the shells. A very little lubrication
will keep them from sticking.
Let us know how it goes. BTW, I bought my jar of lanolin on Amazon. A lifetime supply cost me around $10 I believe. As it said, very little is all it takes.
Warren