I'm planning on purchasing a Lyman deerstalker side lock percussion. I have handled several muzzleloaders at gun shows and gun shops and it seems that every single one has significant rust in the bore.

As soon as I see this I just put them down and move on. Tell me this isn't normal with proper cleaning and lubing?

Is it still the norm to use hot soapy water?

I just took some endoscopic pictures of my .58 caliber rifled musket, .54 caliber 1859 Sharps infantry rifle, .50 caliber Hawken, and 1874 Sharps in .45-90.  Unfortunately I can't get the app to cough up the pictures to post.  In any case, the .45-90 shows some leading indicating the alloy in the last batch of bullets was off, the others so nothing more than very faint traces of patina here and there in the bore, particularly at the base of the lands, but no active rust and no pitting.  With a naked eye, rather than the harsh light and magnification of a bore scope, you'd call them rust free.

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There is no excuse for any significant rust in a muzzle loading rifle.

Hot soapy water works fine along with a bore brush and cleaning patches. A bore mop or patch over a jag can be used to both remove the now wet fouling and also pump water through the ignition path.  

Once you are done cleaning with the hot soapy water and are only getting clean water out of the bore, you should rinse the bore with water as hot as your tap will produce and then rinse the outside of the barrel until the barrel is thoroughly heat soaked to the tap water temperature. Then use a few dry patches to remove any water droplets from the bore and follow it with a heavily oiled patch.  Set it aside and let any remaining moisture evaporate due to the heat in the barrel.   Once the barrel is cool, clean and oil it like you would any other firearm.  Since the compounds that cause rust will leach out of the steel over a few days are hygroscopic (attract moisture) and will start producing rust, clean the bore again with some cleaning patches and oil again after a few days - and then again few days after that if you plan to store it for long periods.  


If you don't want to take the barrel out of the stock, or if you have something like an 1874 Sharps that you are shooting with black powder (as God intended), you can use a black powder solvent to clean and neutralize the corrosive compounds instead of hot soapy water.  

It comes down to preference.  On a Hawken, rifled musket, etc where the barrel is quick and easy to remove I use the soap and water method because it's quicker and easier start to finish.  On my 1859 paper cartridge Sharps and 1874 Sharps in .45-90, I use the black powder solvent method to avoid getting any water on the wood.  However, I'll still periodically detail strip them and ensure any metal covered by the wood gets cleaned and oiled periodically to prevent any rust from starting.  

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I also use black powder solvent on my PSL and M59/66 after shooting corrosive ammo through them, particularly in the barrel and gas system.

+1 on the hot, soapy water treatment, flush the barrel with boiling clear water and liberally oil it while still hot.
If you don't want to pull the barrel every time you clean it do this- get a piece of tubing (silicone RC fuel tubing works well) and slide it over the nipple. Drop the free end in your pan of hot soapy water. Using a snug jag/patch combo you can pump the solution up into the bore and give it a good douching.
For soap I always liked Ivory flakes, good clean and pure soap.

I do the hot soapy water follow by a steaming hot water rinse. Shake to dry. The hotter the water the quicker the barrel dries.
I then run Thompson Bore butter if it is a  muzzle loader or a mineral base oil if it is a  cartige gun.
On pistols I have an old  roasting pan that I submerge the whole pistol in some hot soapy water. I do strip the pistols down and leave the grips out of the boiling water.

Ok guys I got the Lyman Deerstalker ordered 50 cal percussion

As said this is my first muzzleloader.

Any special supplies I need to pick up for cleaning / maintenance?

I have shot some corrosive ammo in a couple of my rifles.  I found an rifle bore cleaner called Black Off, for black powder cleaning and it works great for me.

Corrosion can be more of a problem if you live in a humid area and less if you live in a dryer area.

I've not had any issues with corrosion after cleaning with the Black Off and then running an oily patch through the barrel.

I can say that the one time I had corrosion it was less than 24 hrs. after shooting the rifle.  I finished up at the (out of state) range around 5 PM on a Saturday and drove the 3 hour drive back home.  The next morning I took the rifle out of the case and couldn't get the bolt open.  It had rusted up in just a few hours.  Prior to that I was having no issues at all and had let the rifle sit a few days between shooting and cleaning on more than one occasion.

The point is, don't take chances.  Clean it as soon as possible after shooting it as sometimes bad things happen quickly.

Might be jumping into this late, but clean your bore with either hot water/soap or any other decent bore cleaner you like.  I use a mix of oil soap, water, and WD-40.    Dry well and use a good modern bore preservative.  Go back a day or two later to check for rust.

"Bore seasoning" is a marketing ploy promoted by the folks who sell "natural" lubes.  If your barrel is made of cast iron that you slowly bake pizza in it might work.  Modern steel doesn't season under  shooting conditions.    I would much rather use a product designed to prevent corrosion (Isn't petroleum a naturally produced product?)

HOT soapy water, rubber hose, large tight patch on the ramrod that acts like a water pump, pull water in and push it out, it will clean the path from the cap nipple to the muzzle,  
Dump, and air dry then light oil.

For what it’s worth...I went to waterless cleaning a few years ago and have wondered ever since why I felt the need to do all that work or make all that mess.

I think, this time, I will finally copy & paste this post into a .txt file on
my hard drive in order to save me having to type it out every time.

Obligatory keywords for search function follows..
blackpowder rust cleaning muzzleloader flintlock percussion cap ball pyrodex goex swiss
ramrod cleaning jag dry patch wet patch oil patch frizzen tumbler bridle mainspring fly pan bloche
drum nipple holy black

My background in blackpowder goes back about 30 years. I have used the same method for
cleaning in all of those years, and it has never - not even once - failed me & allowed rust
to develop in any of my bores.

The most important part of this starts the minute you are finished shooting... Clean
your bore then, NOT the next day. At the very least, run some type of solution down
the bore to get the fouling out & then dry patch it until it comes out dry, and then oil
patch it.... that will keep you out of trouble until you get home.

The cleaning solution...
1/2 cup of Murphy's Oil Soap
1/2 cup of Isopropyl Alcohol
1/2 cup of Hydrogen Peroxide

Mix it with a spoon.

Soak a patch in it, and put the patch over a very snug-fitting cleaning jag.
Run it in & out of the bore. Repeat this process until the patch comes out
clean, using new patches every time. The hydraulic flushing action is the
best; Put a small rubber hose over your nipple if you have a percussion
& let it pull from a reservoir.

Once the bore is clean, run dry patches in & out of the bore until the bore
is truly dry. Next, oil patch it twice. My preferred oil is Rustlick 631.

The next day, run another oil patch in & out of the bore. You are finished;
put the rifle away & rest easy.

Here is how good Rustlick 631 is on a muzzleloader bore.... I had to store
my .54 caliber in a wood-stove heated & non-airconditioned old farm house in
which I lived at the time. I did not fire that rifle for about a year & a half,
but to this day there never was & never has been any rust in that bore.
If it can beat the sometimes high humidity in NE Georgia under the conditions
above, my guess is that it can handle it anywhere.

It takes me all of about 4 minutes to clean my bores.

I always rinsed with boiling water first to dissolve all salt and soften fowling. Then the soap followed by several rinses with boiling water. All water evaporates.Then apply oil.

Reason I start with clear is some soap and salt make a sticky sludge. Best to get all salt out first. I clean corrosive like this as well as BP. Corrosive is where I got the sticky crap.

I used to get my hot water with a old coffee pot just put water and turn on.  Yes the hose on the nipple to a pot of hot water works well.  At a civil war reenactment we would use a field coffee pot heat water on the fire wash out the barrel the oil but we used only regular black powder and had no lead in the guns

My two (long unused now and still unrusted) sidelocks got this...

Milk jug in utility sink. Top of jug cut out. Put in a dash of Dawn dish detergent. Fill jug with warm water. Remove barrel, then it's nipple and put that breech end in jug. Nipple also goes in jug to soak. Put cotton mop tip on cleaning rod. Push mop to breech, then pull it out to draw soapy water in the bore. Usually let the water work to start breaking up salts and lube.  Wire brass brush goes on cleaning rod. Bore gets several strokes to knock off clinging stuff. Next is loading jag and a tight patch. Use it to draw in more water and push out most of the bad stuff. Also, the inside of nipple channel on the drum gets scrubbed with a pipe cleaner. Also use same pipe cleaner to work on the nipple that has been soaking. Chunk pipe cleaner and set nipple on a dry paper towel. I dump fowled water down drain and refill with clean hot water. Pour in bore.  Next, I'd blow into the muzzle end after wiping the muzzle with a clean wet paper towel, breech down to push any remaining water out of the drum. Dry exterior of barrel, then run a few dry patches down the bore until patches come out white as they went in. Let it set a about five minutes to make sure the barrel is bone dry, then a Ballistol or Bore Butter soaked patch went in the bore. Used an Oxy/Acetylene torch tip cleaner to make sure the nipple was not clogged, then  a dab of Neverseize on the nipple threads and it is replaced.  The hammer and stock area around the hammer were wiped with a clean damp rag to remove flash fouling, allowed to dry, the get a coating of Ballistol. Reinstall barrel after using same Ballistol patch to coat it's exterior.

I've not used my sidelocks in years since my eyes suck now, but I will bring them out about twice a year and re-Ballistol them, inside and out. I once let them set for a full year without a reoiling, but did not see any rusty patches coming out of the bore.

The post above mine is great information.

I can't prove it, but I think pyrodex is more corrosive than black powder. If you can shoot black, use it.

I've had a .54 sidelock for 30 years. It has some light corrosion in the barrel from the first 5 years I had it and shot a bunch of Pyrodex. That was back when I believed the propaganda about bore butter and seasoning and didn't clean perfectly every time I shot it. It still looks nothing like the used muzzleloader rack at the gun store

Now I hot water clean it every time it is shot, then dry it thoughly. I then coat it with Ballistol. I'll check the bore with a Ballistol patch the next day as well.

I detail stripped my 1858 New Army revolver for the first time in the 8 years I've owned it this weekend. I found some fouling in the deep recesses, but no corrosion. It has been shot 95% with black, and cleaned with hot water and Ballistol every time. I'm happy with the results.

Correct me if I'm wrong, but as I understand if your barrel is made of 12T14 steel then using hot/boiling water will cause "flash rust" in the bore that is nearly impossible to get out. I did this to my Pedersoli Brown Bess. I know it's a smoothbore, so perhaps they don't use this steel in rifles?

Anyway...that's what I was told: boiling/near-boiling water evaporates super quickly and creates flash rust that takes a lot of elbow grease to remove.

Thoughts?