So, here's where I'm at with it: Did a takedown and got the barrel out. Surface corrosion at the bolster (yeah, I've been reading) You have indeed..congratulations..! is a little more significant than the pic shows. Minor surface pitting as a result at the bolster and where the barrel sits against the tang. Got into it with some fine steel wool to get it stopped and get some oil on it, but as expected, it's damaging the bluing (I expected I might have to have that redone anyway, there's surface up around the muzzle as well, I'll worry about serviceability first and appearance later). Got the nipple out, but had to wrench on it pretty good. I think the threads into the bolster are OK, and after cleaning, nipple goes back on and tightens, but I'll probably replace the nipple. Nipples are a "wear part" on caplock rifles. Yours takes a 6mm nipple, available from any company selling BP supplies. Pull the nipple whenever you're cleaning the rifle after shooting. Get it clean inside, make sure the little hole in the bottom isn't plugged, then apply a tiny amount of anti-seize on the threads before re-installing. As I understand it, that's a commonly replaced item anyway, seems like. What I have here is a low time, low use rifle, but as you said, horribly kept/stored. I did what most of the videos suggest. After some good copper brush scrubbing of the insides with Hoppes 9, Rem action cleaner (I don't have any Ballistol) Ballistol is great stuff, IMHO. Hoppes makes a dedicated BP cleaner that is also well regarded. There are others. The key is to use something that offers water solubility because the most effective cleaner for BP residue is water...use it, then finish up with one of the others. and watching all the brown liquid coming out, I boiled a pan of water and ran it through with a funnel. Wash, rinse repeat 2x more times. I'm pretty happy with how the barrel looks in as much as I am able to see it. You'll get varying opinions about using boiling water in your bore. I've been using it on my T/C rifles (they allow me to easily pull the barrel off the stock) with ZERO issues since the 70's and the bores are in like new condition. I clean with tap water that has a drop or two of Dawn liquid in it. Once the bore is clean..I pour a cup of boiling water down the bore. The barrel gets too hot to hold without a kitchen mitt, which is the object of using boiling water, things dry right away. The key is to follow up IMMEDIATELY with a water soluble oil/water displacement product ( I use Ballistol) and swab the bore to preserve the bare metal inside. People who use boiling water and fail to immediately follow up experience "flash rust" that's not good, but can be avoided. Be very careful using a brush in the bore of a BP rifle. On the Muzzleloader forums it's fairly common to read of a new shooter using a brush in his rifle...then coming on the forum for advice on how to remove a brush that is STUCK solidly inside the rifle. I've been shooting BP rifles since 1975 and have never used a brush in the bore of any of mine. Once the bore is clean and dry...you can use any good gun cleaning product to preserve it. I choose G96.
My problem right now is this: I want to inspect and clean this barrel from the other end. But, until I get some more expert knowledge here, I'm hesitant to go further into a teardown. To help inspect the bore...I use a tiny little light, sold at sporting goods stores for lighting up fishing lures. Turn it on, and drop down the bore. So, two questions: Is the bolster removable?
It is, but Don't that's not necessary. What is the screw on the outer part of the bolster, does that serve as a kind of maintenance port for cleaning? Yes, that's a "cleanout screw". It's not necessary to remove it for any routine cleaning. I haven't removed any of mine in a few decades. Folks who attempt to remove them, often end up doing more damage than any extra cleaning would justify. If so, it ain't budging, which makes me wonder if the bolster itself will need replaced. Second is the breach plug. This barrel has the hooked plug, and the question here is also whether or not that is removeable. It looks to be threaded, but again, I'm hesitant to touch either the plug or the bolster, since I suspect these items may need to be indexed when installed. The breechplug is removeable but doing it correctly requires knowledge, and in a lot of cases some special equipment to get it done without damaging the barrel. It is a LAST RESORT to resolve problems ( such as a stuck brush) before just replacing the barrel. Seems to be true at least for the bolster, otherwise the nipple won't align correctly to the hammer cap, correct? That said, I REALLY want to get into the back side of that barrel and insure it cleaned up adequately. I can't get a light in there to see it end-to-end. (See my suggestion, above about using a fishing lure light) I won't consider it safe until I can verify that the corrosion hasn't harmed it back there internally. I'm big on visual inspection, and after talking to my stepdad some more, this looks to be a case of it sat for ~30 years unused and not properly prepped for storage. Mostly I'm worried about that bolster and that outer screw I can't budge.
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