Gun oil has no place around a watch. Gun oils are designed to spread, exactly the opposite of watch oils. Wipe the threads of the tube and crown with an alcohol wipe or clean them with Rodico. The crown and stem can be soaked in Naptha and rinsed in alcohol, with or without use of an ultrasound cleaner. Then use silicone gel lubricant on all of the O rings in the tube, outside the tube and in the crown. Removal of dirt and debris is what ensures smoothness, adding oil just creates debris paste. The square part of the stem tip should get a couple drops of watch grease if it is removed and cleaned (moebius D5 or Molykote dx).