Blowing after every shot with Swiss powder does not result in a build up of fouling for me. I can continue shooting over a hundred shots without wiping or cleaning.

To clean I use 10 % Kutwell water soluble cutting oil mixed with 90% winter windshield fluid. No need to heat up. Two or three wipes cleans my barrel. Then I run dry patches through to remove excess fluid. 

A 10% mix with Ballistol will do the same thing.

For humid areas some people use WD40 to coat the barrel before storing. I wipe my barrel with bore butter after I clean.

If you have hard carbon fouling a warmer solution may work better; but I do not seem to get any hard fouling since I blow after each shot.

If you are getting hard fouling after blowing on each shot then your lube may not be performing as well as it should; or your powder may not be burning sufficiently.

I also use magnum primers to help burn or clean up fouling that would be left by unburned powder.

Schutzendave
Winter Windshield wash contains a certian amount of METHANOL in from my understanding (I could be wrong for sure on that) and from what I have seen with methanol at work that shtuff corrodes even stainless steel.  It is definetly not steel friendly.
Methanol mixed with water 35% methanol to 65% water is good to 35 below zero.

I use straight water and drypatch then bore butter.

Ken.

Fred Boulton wrote on Feb 15^th, 2011 at 5:11pm:


I don't have experience with methanol corroding steel, but we used to run a couple of drag cars on methanol. All of the seals and the fuel cells had to be reworked or the methanol would dissovle them within a few hours.

Chris.

"Why blackpowder has a reputation for rusting bores is twofold.  One, the fouling is hydroscopic, and absorbs moisture from the air.  That moisture causes the rust.  Two, old time primers were very caustic.  I think that the primers contributed as much to "blackpowder rusting and pitting" as did the powder residues."

You make some very good points, Dave.  If you look at antique flintlock rifles, they don't show near the pitting and erosion on the outside of the barrel at the vent as percussion rifles only a few years younger do around the nipple and drum...the difference being the corrosive effects of the percussion caps in use until relatively recently.

David

Forget about the acid thing - BP fouling actually is pretty alkaline, no acid anywhere, even when mixed with moisture.  Very easy to test...

I'll refer to a quote from Bill Knight AKA "the Mad monk" on BP fouling and more specifically re. this 'urban myth':

"The idea that black powder combustion produces sulfuric acid is a lot of nonsense.
The residue left by the combustion of black powder in the gun is highly alkaline. Collected bore fouling showed a pH of around 11 in a few of my tests. Potassium carbonate, or potash, is the primary solid product of powder combustion. Roughly 3 to 4 parts of potash for every part of potassium sulfate. As soon as the fouling picks up even traces of moisture any sulfurous or sulfuric acid would be neutralized.

The charcoal used in propellant grades of black powder will show fixed carbon contents of 65% to around 80%, depending on the source of the charcoal. If the charcoal had been heated above 320 C during the charring there will be no liquid hydrocarbons remaining in the charcoal. When charred at 320 to 350 C there will be measurable amounts of liquid hydrocarbons remaining in the charcoal. Some chars may be 6 to 10% creosote by weight of char. The liquid hydrocarbon(s) then being the source of water as a product of combustion. "

But - with a pH-indicator, anyone can do these tests...

Someone correct me if I am wrong, But would not this test be simple as Litmus paper on a water wet patch that had been run through a fresh fired bore. I had always believed the sulphuric acid story and used an alkline cleaning solution. Maybe I learned something.
Chuck