I am a firm believer in Perma-tex superlube. It is clear, has teflon in it, and is actually food grade. A thin film of this stuff, will do the job, and not transfer color to other things.
I keep a tube of this grease in my shooting box, just because I have been on the range so many times, and had new shooters with dry locks have "mechanical breakdowns". A little superlube has saved the day more than once.
Hungry Horse