Hey, look into "solid film lubricant".....Sandstrom products invented the stuff with the input of some Army science & engineering "dudes" I know. The Army uses it for touch-up finish on many weapons.
Surfaces must be completey clean, dry & oil free. The coating is resistant to common lubes and has good wear resistance. They make a pen that looks like a magic marker....easy to use & reapply if needed.
Best,
Slim