I am deferring to more learned minds for information on this subject. There has been quite a discussion on using tranny fluid in conjunction with a ML. I shall not attempt this while in any degree of sobriety. My query regards the use of mineral oil as a patch lube. It has had the snot refined out of it, to the degree it can be taken internally as an, ah, "intestinal lubricant". It is always stated, and I'm not sure why, that no petroleum product should be used as a patch or bore lube for a black powder gun. They are used for centerfire arms, so it can't have anything to do with burning temperature of powder setting the lube on fire. Or something. The amount in the bore would be so small as to not be a danger to comtaminating the powder charge if removed properly before shooting. Besides, any other liquid lube would run the same risk. Mineral oil just looks like it would make a great patch lube, even better than for relieving "distress in the lower tract" as they say on the tube. Just why can't petroleum products in general, and mineral oil in particular, be used as a patch lube? Inquiring minds want to know.