There is a company called LPS that makes a product that will remove the cosmoline withoout hurting the wood. The produce is LPS #2. For the amount of surface you got to clean(All them Rifles), I suggest getting a 5 Gallon can so you can dunk the parts. One place I know handles it is W.W.Grainger.
Bruce Shiverdecker - Retired Starving Artist ( No longer a Part timer at Woodcraft, Peoria, Il.)
"The great thing about turning is that all you have to do is remove what's not needed and you have something beautiful. Nature does the hard part!"