Being a lube/corrosion inhibitor junky (strange, I know) I looked up its Material Data Safety Sheet. Too long to post here. They've done some strange stuff with it, like fill up the GI tract of small creatures with it, and after evacuation, the animals appear to suffer no adverse effects.
But the ingredients are:
Mineral Oil
Potassium Oleate (surfactant/emulsifier)
Ammonium Oleate
Oleic Acid (fatty acid/oil)
Benzyl Alcohol
Amyl Alcohol
Isobutyl Alcohol
Benzyl Acetate (organic compound used in cosmetics for aroma; solvent)
Anethole (natural aromatic compound, smells like anise/licorice)
Isohexane (aerosol only)
So as best can tell (its been 25 years since I studied organic chemistry) the mineral oil and oleic acid provide lubricity, while the alcohols and perhaps the benzyl acetate are solvents.
So in some respects its action is similar to WD-40 (mineral oil for lubricity, mineral spirits for solvent), but Ballistol has a higher pH which neutralizes acids in gun bores. And Ballistol mixes with water (because of the emulsifier), which is beneficial in some applications. A person I contacted at Ballistol assured me that it is nothing like WD-40.
I have not tried the stuff, but I will.