If you haven't tried Slide Glide yet, you may want to give it a shot. It's one of the best greases I've ever used. Also, according to a test I read a while back (I can't recall where, unfortunately), it exhibited some great corrosion protection properties as well. I use it on the action bars of my shotguns (when the weather is not frigidly cold), and I also use it on some of my tighter fitting handguns (1911's, Sigs, etc.) and it does a great job. You can also get it in different weights, depending on the application.