This is a subject that comes up frequently and there always seem to be good advice, mediocre advice and out right bad advice. So I'll put up my method that I gleaned over the past 36 years of shooting real black powder in various forms and discussions with serious BP target and recreational shooters.

The real purpose in cleaning BP fowling is really 2 fold. The primary reason is that BP fowling is hydroscopic. It will attract what moisture is in the air and then that moisture will cling to the fowling that is clinging to that bare steel, those causing rust. The secondary reason for cleaning is that BP fowling is heavy and will eventually effect the functioning of the firearm, especially in percussion ignitions systems.

The first issue is one of water. Many put up the old advice of using hot water, even boiling water, and I heard the same thing when I was younger. I've since learned there is no advantage to using hot water and a very real disadvantage. Hot water, especially if it's beyond comfortable touching levels, does in fact increase the risk of flash rusting. Flash rusting in and of itself is not a serious detriment if it only happens a time or two, but if repeatedly allowed to happen the barrel will become frosted from pitting and loading ease will suffer, as well as eventually effect accuracy.

Second issue is soap. Ok, soap does not hinder the cleaning of any firearm, muzzleloader of other wise, but I've never found that it makes cleaning any faster, easier or even cleaner. Water seems to get the job done with or without soap added. And with this subject comes the various concoctions people seem to dream up, ie, moose milk in it's various formulas and others. Why? Water is cheap and water is simple and unless you are going to snort it, water is safe.

Third issue is preservative oil. Ok, you've just spent the last 20 +/- minutes cleaning your smokepole and now it's got dripping water everywhere. What will you use to git rid of all that rust causing water? The simplest method is to dry patch the excess out and them use an oil to displace it in the nooks and crannies everywhere. Well, an effective method is to use WD-40. I don't like the stuff for firearms usage, but it does work, and you do have to remove the excess before you put away your gun. I now use Ballistol, either straight or mixed with water, but for the bore the 75/25 mixture is easier to work with. Yes, it does stink, and smells even worse with BP fowling, which is why I don't use it until I've cleaned the fowling out. With the Ballistol mixture, the water will evaporate and leave the oil behind and over the past year and a half, I've yet to have any rust show up by using this method.

Methods to use for cleaning. The obvious rags and brushes to wipe down down exterior surfaces is obvious enough to not need repeating here. Now on the subject of cleaning bores. If you have the type of ML that has the wedges or keys to allow easy removal of the barrel, then by all means remove it and put the vent end in a bucket of clean water and use the hydraulic pump method to clean it. There is no other method that will clean as well as this one. It you have the old pinned style barrels that were quite common on many original style flintlocks and even the cheaper later styled percussion rifles, the you will need to plug the vent with a small feather or toothpick or cap the nipple and pour some water in and slosh it back and forth with your finger plugging the bore. It's funny looking and can be cumbersome with some of the longer barrels but it does work. I actually just use a cleaning rod and wet patches on jags, or my absolutely preferred method is Tow and Worm. But that is a discussion for another time.

In parting I will add this, since it comes up frequently. If you have removed all the black colored fowling soot and you are still getting great stains on your patches, that is the graphite Goex uses to coat the powder to lessen static issues that can be had without it. Don't obsess over that gray residue, it's won't hurt a thing. Now if you get orange residue, something is afoul, and it's probably rust caused by something.

Cliffs: 50/50 Ballistol and water cuts black powder fouling fast.  100% Ballistol prevents rust.

Good points.

Yes it does. Water is still cheaper.

I don't like WD40 or any petroleum based oils on my Black powder guns.

I used hot water a little DAWN dish soap, then oil with ballistol

I like your cartage for your pistol.. Nice job!

Ballistol is mainly mineral oil, mineral oils is a petroleum based oil. However it is a paraffin oil which works fine with BP

When I used to shoot N-SSA, I read the pamphlet written by Major Hardee, then USA, on care and handling of the musket. They used boiling water in the barrel, then dry patched it and some oil. So I would take a small thermos and a plastic funnel with me and after plugging the nipple with a patch, pour hot water in and slosh back and forth until when I poured it out the water was clean. Never had an issue with rust and the bore always looked great.

With my capnball revolver, I use a 10:1 Ballistol/water mix as recommended by duelist1954 on YT. Cleans everything up nice and easy, and a light application after keeps the rust away. I usually spray the bore, cylinder and the whole gun with it at the range, then wrap it in a towel for the 20-30 minute ride home. Then right into the "man cave" and have at it.

You can go by the writings of recommendations from those that had not the technology to scope a barrel, or you can go by recommendations from many of the finest custom makers alive that repeatedly say not to use hot water. Choice is yours and it's your money. I also know first hand from working in industrial machining and repair, that water too hot to comfortably touch will indeed flash rust steel.

Actually I am going by the experience I have as stated, as well as the posts from YT  from someone who has been shooting cap and ball revolvers for 40 years and is a graduate from gunsmithing school. Also, the manual I read is a direct copy of the one written before the ACW and used by BOTH sides to clean weapons after a fight.

I have no long guns right now, but when I do I will continue to use what has worked. For my handguns, the Ballistol/water mix sits in a spray bottle, no heat needed.

A gunsmith that tells you to use boiling water on bare steel is an idiot. I copies of those old Civil War manuals, along with metal working and machining books that go back before that period. Military guns got used up quickly in service largely from poor cleaning methods, and that is a simple fact. No heat needed for any cleaning.

OP I agree completely.

Cold water works just fine. I frequently use the kitchen faucet or garden hose to clean my BP revolvers. Followed by quetips to clean the chambers and some patches through the barrel.

I've used whatever gun oil I had on hand to include WD40, Remoil, and now Ballistol.

I too use the bucket / plunger method for cleaning my rifle.

For years coached the local 4-H Shooting Sports blackpowder discipline. Used the 1:10 Ballistol mix for cleaning, then dried everything and coated with straight Ballistol. The 4-Her's did the work themselves at the end of each weekly practice. Over the winter all the guns were stored in their foam padded cases, but first were heavily coated with straight Ballistol and then covered with that press-and-seal saran wrap type plastic. That way the foam didn't soak up all the preservative.

This has changed my life.  This formula is NOT safe for finished wood but works fantastic on metal and black powder fouling.

Equal parts of:

1. Hydrogen peroxide
2. Isopropyl alcohol
3. Murphy's Oil Soap

It cleans and neutralizes the fouling and the oil leaves some protection behind.  I do follow up with Ballistol afterwards because I know it prevents rust.  

I wish smokeless cleaned as easily.

Why make a concoction that is not wood finish safe, when water or Ballistol/water mix is? Simplify your life and ditch the moose milk. BP fowling does not actually need to be neutralized, it needs to be removed. Its literally just soot until it attracts moisture which causes the rust, which causes the eventual pitting. Water is what removes it, oil then protects the bare steel.

I clean my BP guns at the range.  This way there's no going home and getting called away from the task.
In my experience hot water works much better than cold water.  I used to bring a camp stove, water and a pot to heat it in to the range.  This is in addition to the other shooting and cleaning related items.
I read about the concoction and gave it a go.  It works great, very quick to cut and remove the fouling.  So now I can leave the camp stove, pot and water jug home.  I do now apply Johnson's Paste Wax to the stock of my rifle before I clean it.  It's an extra step but I'm happy with the trade.  

I thought moose milk was water soluble oil and water.  Which isn't a bad concoction for BP maintenance.  However, in the mixture above the peroxide is an oxidizer and the alcohol is a needless degreaser.  The soap would be useful to reduce the surface tension and promote wetting of the bore surface. Lots of water and a hint of soap followed by oil for rust prevention has worked well for me for years...

Most moosemilk recipes I've seen over the past 30 years have involved MOS in some fashion, and usually 3 ingredients, but sometimes 2. I'm sure that some could refer to Ballistol and water mixed as moosemilk as it is white like milk. I clean my BPCR brass in water and soap, but have not found soap to really make cleaning the bore all that much easier, but it doesn't seem to hurt anything. Soap is great for degreasing. I've yet to figure out just how peroxide would help get my bores any cleaners than they already get with just water, or water/ballistol.

Hot water does not bring anything to the table, except for the possibility of flash rusting. It's the water, not the temperature that does the cleaning. Really hot water will strip the oils out, which is why the flash rust, cooler water does not do that. It takes me exactly 2 wet patches to range clean my muzzleloaders and one to oil. And just why do you need to wax your stock?

I have been shooting black powder for a mere 16 years, and I always feel like there ought to be a better way. 1:10 ballistol works well, hot water with dawn works well (the heat helps it dry quickly, and with a little ballistol, no flash rust), moose milk works well. I tried putting my ‘58 new model army in the ultrasonic cleaner and it actually didn’t get much of the fouling off.  One thing I have found that makes it easier is shooting a smoothbore. No rifling to clean.

36 years for me. Yes, if you use water that is hot enough to flash dry, it will leave a light coat of flash rust. Been down that road many years ago and always wondered why my patches came out with rust traces a few days later. Never happened again since I went to tepid water.

Dawn detergent and water or Ballistol if I am at the range for me / never had an issue for decades.

Corrosive salt is what you are trying to neutralize or wash away and good old water does a great job.
Water and salt are polar compounds and attract each other .

Corrosion is accelerated by available moisture in the air content so a state with high humidity Vs in a desert area impacts how fast something starts to corrode.
Guns made of stainless steel also rust if a magnet sticks to them ( contains iron ) so always clean your gun.

Why do some BP shooters not like using Pyrodex as opposed to real black powder?

Are there differences between them in terms of the cleaning regimen?

I never had a problem with Pyrodex until I moved to Tennessee with it's very high humidity. After shooting one humid day, I cleaned my rifle as I normally would with water and Balistol and oiled the whole thing down with Balistol after drying the barrel out. The next week I checked on it and there was rust all over the barrel inside and out. Had to scrub it all down and reclean and oil again. I don't know if just using Balistol alone without water would make a difference but I think the humidity was the main factor. Since then I have only shot real Black powder 2F and 3F and I have not had rusting but it hasn't been very humid this time of the year in January and February.

For me, the issue is perchlorates, which will induce rust pretty fast in bores. It also does not work in flintlocks.
BP soot is just dirty, it's not actually corrosive, it is hydroscopic, attracts moisture which causes the rust.

BP is more consistent , IMHO.
I was accuracy testing in an inline muzzle loader and my BP loads were more accurate and lower velocity deviation Vs Pyrodex.

I cleaned the gun the same and did not notice any difference.

I got away from hot water. I just keep using tap water till it is clear. Then I dry patch follow by WD40 . I dry patch out the WD40 follow by a wet patch of balistol. Close to what the op does.

With a revolver, it took longer for the fouling to build up with Pyrodex. It gets pretty tough to load my 1863 after around 50 shots with BP.

Pyrodex fouling wasn’t really any easier to clean. I also found ignition was far, far more reliable with BP. Didn’t matter which cap was used, the Pyrodex had constant hangfires and misfires, the BP was 100% ignition.

Substitutes are far more available and less regulated than BP.

Why is BP more regulated than either the substitute, or smokeless powder?  Isn't smokeless far more powerful than BP is?

Also, if hot water can cause flash rusting, then is this an issue with an ultra-sonic cleaner, which heats the water up to decently hot temperatures as well?  I know even my wimpy 2L Horaday one gets the metal to don't want to touch it hot.  It does also make the water evaporate away quickly, which is nice.

When I used the above  same 2L ultrasonic cleaner for my non-black powder parts and suppressor baffles, I noticed it would remove all the oils, etc from the pores and crevices of the parts, which would promote rusting. Makes sense. I followed up with placing my parts and baffles in near boiling or the oven (250 ish degrees) with cooking, olive oil, etc right after removing from the ultrasonic cleaner. Really helps with the baffles, but its mainly from cooking in the oil IMHO.

My local gunsmith was big into black powder competitions for years. Always searching for a better method. He uses Denatured alcohol and Murphy’s oil soap concentrate mixed 3:1 works very good and is super cheap. Puts it in a spray bottle uses it on everything.

I've been using hot soapy water followed up by CLP for over 30 years and have never had any problems with rust.

I use 50/50 rubbing alcohol and vinegar, seems to work well. I oil the bore afterwards.

Ok, so I'm not doing it right? I scrubbed the bore with Hoppes #9 until it came clean then a patch with Weapon Shield on it. Wiped down the entire exterior and arbor with Weapon Shield. I sprayed Gunscrubber through the cylinder after removing the nipples, then sprayed the nipples, and used the nipple pick. Cylinder then was scrubbed out with a chamber style brush and Hoppes, then a light application of Weapon Shield to every surface. I don't SEE any rust, but Arizona is pretty darn dry and I don't have a swamp cooler. Then I finish up with MetalGlo on the brass - I like a shine.
Not the right way?

Considering Arizona you could probably get away with just about anything, and everyone has their pet way to clean black powder. Most of the methods listed above will work just fine. Personally since there is so much crud to clean I prefer to use cheaper solvents to get the job done.

If you getting it clean then it’s working. Just try to remove any petroleum based residue before you fire it again, with the exception of mineral oil. On the other hand, you could clean it cheaper with room temp water and pocket the savings from not buying solvent. BP fowling is nothing more than hydroscopic ash. No real need to get too fancy.