The Shrink, I respectfully disagree.
I also learned many years ago to NEVER use any petroleum products with black powder, lest the two create a hard, tarry fouling that stubbornly resisted cleaning and affected accuracy.
But the canning paraffin I use, while is decidedly a petroleum product, does not have this propensity.
More than a year ago in one website (this or another, I can't remember) I posted the recipe for a paraffin, mutton tallow and beeswax bullet lubricant, which dates to the 19th century.
It caused quite a row, since many like yourself pointed out that paraffin was a petroleum product.
Along came a chemist, who explained that paraffin either lacks or contains the hydrocarbons that somehow make it significantly different from petroleum greases and oils.
I can't recall the explanation, it was technical (and I have trouble figuring out how to open a can of sardines) but his assertion was that paraffin did NOT create the hard, tarry fouling of which we are all familiar.
And my own experience confirms it.
The old-time recipe is:
1 part paraffin (I use canning paraffin. Dunno how candles might work)
1 part tallow (I use mutton tallow, sold by Dixie Gun Works)
1/2 part beeswax
All measurements are by weight. I use a kitchen scale to measure 200/200/100 grams of ingredients, which nearly fills a quart Mason jar.
With the weighed ingredients in the jar, I place the jar into three or four inches of boiling water for a double-boiler effect (the safest way to melt waxes and greases).
When all ingredients are thoroughly melted, stir together with a clean stick or a disposable chopstick. Allow to harden at room temperature. Hastening hardening by placing in the refrigerator may cause the ingredients to separate.
I've used the above recipe for about three years and have lubricated felt wads, lead bullets and rifle patches with it. It has worked extremely well and never caused the hard, tarry fouling that is the bane of shooters who use petroleum products with black powder.
I'm no chemist. I can't explain it technically but I do know that --- contrary to all claims --- the paraffin in this lubricant is beneficial.
I believe it is particularly beneficial when felt wads are soaked in the melted lubricant. After the wads harden at room temperature, they're slightly stiffer than the commercial wads.
This stiffness, I believe, has a scraping effect on fouling. Recovered wads show a negative impression of the rifling around their periphery.
But the real acid-test is a peek down the bore. I can shoot all day, never swab the revolver bore, and it looks almost as though I've been shooting smokeless powder through it!
I've shown the bore to other shooters at the range and they've been amazed.
I hope you understand I'm not trying to flame you. I used to think as you did, considering ANY petroleum product as pure poison when mixed with black powder.
Now I know that there is at least one exception (paraffin). I wonder if there are others out there?