I use the supposedly non-toxic non-chlorinated brake cleaner on bare metal parts of a used rifle when I acquire them. I often find the bargains among the dirtiest, filthiest, nastiest of parts and rifles.
For soaking, I prefer odorless mineral spirits and then a good scrub. I also use things like simple green and its clones for just dirt. For the most part, even a mild solvent/oiler such as CLP will keep stuff clean after the initial purchase as I simply do not get my firearms that dirty.
I always oil after cleaning with anything that removes oil or grease--always.
For soaking, I prefer odorless mineral spirits and then a good scrub. I also use things like simple green and its clones for just dirt. For the most part, even a mild solvent/oiler such as CLP will keep stuff clean after the initial purchase as I simply do not get my firearms that dirty.
I always oil after cleaning with anything that removes oil or grease--always.