I stated I use Mobile 1 Motor Oil on my guns and have for years. Some have mentioned using grease. I do not recommend any grease on firearms. I oil my weapons with a very light coat. Most people over oil rather than use to little. Extra oil and especially grease traps all the carbon and grit it comes in contact with rather than letting it blow or migrate out of the weapon. Drop a dry weapon in the sand, shake it off and the sand falls away. Cover that same weapon in oil or grease and see how much more sticks to the weapon instead of falling away. I understand some guns, like some 1911s, like to run "wetter" to run properly and I would recommend cleaning them more often to get all the crap out of them but in general less is more with firearms.