Before I would go to the time and expense of a small base die , I would check the OL of the cases that are sticking , it may be a tough too long and need trimmed , I would also look at the bullet profile to make sure that the COL is not putting the Ogive into the lands .
Some bullet seating dies are more consistent than others and will very enough to cause a problem with COL , check for rifling marks on the bullet of the ones that are harder to chamber .
stimpy