Bill, Could you explain in laymans terms the difference between petrol wax and petrol oil and grease? And how to know which is in what?
Thanks,
Bill
I'll use Pennsylvania crude oil as an example here.
When they first started extracting crude petroleum oil from wells in western PA they quickly began to have problems with transfer pipes block with this sort of soft slimy stuff. Crude vaseline. Also known as Cosmoline. The base wax is one of a number of microcrystalline waxes and parrafin waxes with some liquid hydrocarbon.
If you take a straight lubricating oil, such as plain old motor oil, add some sulfur and then heat it for about 8 hours you get asphalt, road tar. The lubricating oil polymerized with the heat and sulfur. If you take straight lubricating oil in a metal pan and burn it with a propane torch you see this carbonization and asphalt film formation.
If you take this same lubricating oil and add a bunch of metallic soap, such as calcium or cadmium stearate, you get a wheel bearing grease. That will also quickly form asphalt films in the bore of a BP gun firing black powder because of the sulfur in the black powder.
But the various petroleum waxes, microcrystalline and parrafin waxes will not polymerize and form asphalt films in the bore. Over a long period of time to may see a very thin dark film in the bore but it won't act like asphalt in the bore.
If we go back to the 1970's in ml shooting we had Blue & grey patch and bullet lube. Nothing more than repackaged wheel bearing grease. T/C's Maxi-Lube was nothing more than the same grease they used to grease bearings, etc., or their gun making machinery. Being petroleum greases made from petroleum lubricating oils they would form asphalt films in the bore.
Given the conditions in the bore when you fired the gun the heavest film thickness was back around where the ball, or bullet, had sat on the charge. The film grew thinner as you went towards the muzzle. With each round fired you added just a little bit more thickness to the film. Then a point was reached where you could no longer seat the ball or bullet directly onto the powder charge. Then came a time when you couldn't get either seated on the charge and could not pull the ball or bullet because it was stuck in place in the asphalt film. Somebody would have to remove the breech plug and then use a steel rod and a hammer to drive it back out the muzzle.
Now if every now and then you simply scrubbed the bore out with a tar solvent it would not become a problem. But water based cleaners simply had no effect on the asphalt film. Someting like turpentine or mineral spirits would remove the asphalt film.
This thing about balls or bullets being frozen to the bore off the powder charge was suspected in a number of gun blow ups at that time.
Every time somebody would send Dixon Muzzleloading another sample of lube they wanted to sell to him I would run it through the propane torch test. Put some in a metal jar lid. Out in the yard of course. Then use a propane torch to heat it and burn it. No asphalt, no problem. If it left a sticky black film in the jar lid then you knew it would do much the same thing in the bore.
One still sticks in my mind. We were down at Woody's and somebody had given him a sample of patch/bulklet lube they were trying to foist on the shooters. So I ignited a small amount in a jar lid. When it began to burn it puffed up like a big puff ball mushroom in the woods. No way were we going to use that stuff in our rifles. That was a petroleum grease with a LOT of metallic soap in it.