I had played with Ballistol but did not like it as a patch lube in the round ball rifles.
I think it is a paraffin oil and not what we would normal purchase as the USP Heavy Mineral Oil. The Internet info on it is not that particular as to just what it comes from other than cracking crude oil.
I think it could be the oil extracted from petroleum jelly (Vaseline) when the crude petroleum jelly is "Sweated" to separate out paraffin wax. The commonly used term "mineral oil" covers a number of oils recovered from paraffinic crude oils.
Mad monk
Thanks for the info, Monk ... think I will stay with my mink oil.