I've used brake cleaner with good results. It's non corrosive to aluminum and steel, won't hurt springs, etc. (what it was designed to clean safely on a car). I use the non chlorinated type to eliminate unneeded exposure to methylene chloride. The drawbacks are that it is quite flammable and because it causes metal to get cold, it can make rifle parts sweat. With a trigger group I spray short bursts with time between for the metal to warm back up to ambient. I noticed no condensation with this method.
As far as lubricant goes, I'm looking for something that does well in rain and prevents corrosion yet doesn't get gummy. I'll be using this rifle on the west side of the cascades in an area that averages 100 inches of rain a year and temps typically run 35-45ºF during deer season. Deer season here is often a constant cold rain for days on end unless you hunt on the east side.
"If someone has a gun and is trying to kill you, it would be reasonable to shoot back with your own gun." The Dalai Llama (5/15/01, The Seattle Times)
"That rifle on the wall of the labourer's cottage or working class flat is the symbol of democracy. It is our job to see that it stays there." George Orwell