eyeball, try brushing the insides of your case necks with a bore brush before you resize. A little graphite on the brush wouldnt hurt. You can also apply some case lube to the inside of the necks with a q-tip, the least amount you can put on there will be about right. You can also chuck your expander up in a drill and polish it with some steel wool or a scotch brite green pad. One or all of these things ought to make the expander operate smoother. I usually clean my cases after resizing, that will remove any lube from the inside of the neck. Othewise you might get some powder sticking to the lube in the necks. Try just brushing the necks with graphite first, that will do it most of the time.