Well, these aren't facts, just one person's opinion. FWIW
From:
http://www.chuckhawks.com/lies_muzzleloading.htm
Randy Wakeman
Many of the "truths" that have been parroted for many years in frontloading city are either half-truths or outright lies. It is time to set the record straight, past time, actually. Here are but a few of them, presented for your reading pleasure.
Bore Butter Seasons Barrels
That is an absurd and ridiculous notion. The notion that, in this day and age, a combination of road kill, wax, and "fresh pine scent" changes or protects the surface of a modern steel barrel in any way is without foundation. A century ago, when barrels were iron or laminated steel, good bore protectants were hard to come by.
Sure, lard, bear grease, bacon drippings, anything that was available to coat metal was better than nothing, and was used on far more than barrels. It was used on wagon wheels, hinges, and practically anything that moved to reduce friction. Some of the old "natural" lubes were outstanding, such as sperm whale oil.
Most of us don't do much whaling these days, though, and to really protect the bore of your muzzleloader you need the same properties that work on any other modern rifle barrel, such as Breakfree CLP. Bore butter is "udder balm," handy if your milk cow has a sore udder, but as far away from a high performance metal protectant as can be obtained. Hard as a rock in cold weather, runny as water in the summer, bore butter is better off thrown or flushed than inflicted on a rifle.
