Wood:
There are lots of greases (gun-specific or otherwise) up to the task, folks have posted above several options.
I have used white lithium grease, but did not like how it reacted over time (evaporated & gummed up over time in the heat) or in the cold (stiffened a bit).
Regular applications for use in warm weather, it is just fine, though.
I currently favor this product:
http://www.crcindustries.com/ei/content/prod_detail.aspx?S=Y&PN=05351
Here are the claims:
A specially developed synthetic grease with a high-tech formula for use in disc & drum brake systems. High temperature grease is plastic & rubber safe. Use on metal to metal contact points and sliding surfaces. Resists moisture and will not washout.
Also, the following caught my eye:
Evaporation Rate <1 (butyl acetate=1)
Working Temp -40 to 600°F intermittent
Doesn't evaporate quickly, stays soft when it gets cold, doesn't migrate, water won't displace it, and not too likely to react with any plastic, rubber, or wood (finishes). Oh, and it lubes metal-on-metal interfaces & comes in a handy tube which lasts a long time.
For my own part, I have embraced grease more over the years. I got suspicious that over-oiling might have caused some misfires (by wicking through the primer pocket) and my one titanium-content gun galls terribly when it is steel-on-ti and desperately needs a grease that stays put.
Here is another grease I have had good results with. It comes in a larger tub:
http://www.mobiloil.com/usa-english/motoroil/other_products/mobil_1_synthetic_grease.aspx#
http://www.autozone.com/autozone/ac...s-synthetic-grease-tube?itemIdentifier=934751
Frankly, despite my affection for Breakfree CLP and Hoppes #9, I have drifted more to using synthetic motor oils & auto greases.