Old brass refinishing

[Memornix]

Two questions for an old KP3

First, I am restoring one back to newish and need to refinsh the outside. Does anyone know what the original finish was? It seems very thin so I am assuming it was just paint rather than powder, but not quite sure.

Second, the inside of the barrel needs some more love than just a cleaning. I know is it already going to be over sized for modern paint, so honing it will only make it worse. That being said, any suggestions for a hone or series of hones to make it sparkle again. I have done a series of high grit sandpaper on a dowel stuck in a drill before but I reckon there has to be a better way.. I am planning on doing wedgits to prevent roll out.

[Rusty Brass]

The outer coating is a mystery oxidation process that has been lost in the sands of time. I haven't seen anyone come back with a definitive answer anyway.
A hone won't necessarily take off much in the way of material, not an actual flex-hone anyway. You might, depending on the condition, be able to get away with a nylon or cotton shotgun brush/swab and some Brasso or the like... hard to say without having the gun in hand. Brass cleans up a lot quicker and easier than you might expect though.

[Grendel]

Look up: (this is what you use in engraving to get black on copper alloys)

• Liver of Sulfur
• Selenium dioxide (Gravoxide and Casey Brass Black for Brass/Copper/Bronze both contain Selenium dioxide)

Casey Gun Bluing is different then Casey Brass Black and gives a more blue/purple coating that is not tough at all.

[Memornix]

A hone won't necessarily take off much in the way of material, not an actual flex-hone anyway.

I have been looking at the flex hones you speak of, but there seems to be a ton of grit and material options. This barrel is pretty bad so I am thinking it might be a two step fine/course process. Any experience with different grits and abrasive materials.

[Rusty Brass]

When you say "pretty bad" what are we talking about here? Is the bore stained? Showing hatch marks? Long linear scratches? Huge freaking pits? Was the previous owner shooting rocks and rusty nails out of it?
What are the chances of getting a pic of the bore?
If all you're looking at is a surface patina, which would be my guess, then you can undoubtedly just use a cotton shotgun swab with a drill and some brass polish. Even if the bore is pretty marked up I'd be really surprised if you'd need to go any heavier than the Levigated Alumina - the finest grit they offer. You really don't need an optical quality mirror finish in there and any sort of grit is likely to cause bigger scratches than you're trying to polish away.

[Memornix]

I will try to get some pics. It is possible they broke a bunch of paint in it 25 years ago and let it turn to stone, or it could be some sort of corrosion from something. I used quite a bit of warm water then alcohol and any other cleaner I could fine with squeegees and barrel swabs assuming it was just old paint but it didn't cut it at all. That is why I am assuming something abrasive is in order.

Whatever is in there is definitely a positive growth rather than a removal of material like like deep scratches.

[Memornix]

This should give a pretty good idea of what I am dealing with

[Rusty Brass]

Wowwww. That's crazy looking. I've picked up some ugly brass but that's a new one to me. Almost looks like it's delaminating... which doesn't even make sense. I can't think of a corrosion mode that would make brass look like that, it almost has to be gunk of some sort. Dezincifying normally looks a bit different. Was it green before you cleaned it up? Black? Pink?
I'd try something like acetone (if you haven't yet) before going at it with abrasives either way. Soak it good. If that doesn't get rid of the crud then maybe a scotch-brite scrub and the alumina hone? Don't use any cleaner that has ammonia in it though. That's bad juju for brass.
Maybe we can get one of the old-hand brass wizards to chime in here with a positive ID...

[Memornix]

Yeah, I have done my share of clean ups, but this one is special. It has always been pretty black. I haven't done the acetone yet, but will give it a shot

[WORR13]

wow pretty nasty. looks like gunk to me. prolly old paint grease oil dust etc. give it a good soak in soapy hot water and nylon brush scrubbing, hot water and dawn works best. heat deff. helps alot with brass

[Grendel]

That scaling inside the barrel looks like someone tried to coat the inside of the barrel with something like shellac or some other viscus coating that hardened. I've never seen brass have scale of its own like that and I've seen and cleaned tons of brass in my life time (ex-Navy enlisted ) There was some talk on the old forum about some players trying to add different things to the inside of brass barrels to build up a layer to close the bore. Ty and I both tried to use brass shim stock but both of us were unsuccessful fully. It being that bad I try a brass shotgun brush (16 gauge) with a drill motor to knock some of that down if I could not loosen up with a solvent like acetone or MEK.

[Knuckle Dragger]

If it’s some coating, have you tried a propane torch? Maybe get that stuff to coke up and fall off. Not sure if the front sight bead is soldered on though.