Removing rust

[hortonstn]

I ran a borescope down one of my barrels to my surprise I saw several brown spots I presume it's rust even though I clean with dawn and water then dry out with wd-40 then follow with rig
What's the best way to remove this?

[Scota4570]

Just a little rust? 

Not a big cancerios mess. 

I'd work it over with Maroon Scotchbrite and Semichrome polish.  I'd keep it wet with windex while I was polishing it. 

[Daryl]

Another good one is AUTO SOL Metal Polish. It is a bit more aggressive than Flitz & JB Compound.

[hortonstn]

Thanks guys yes it's just a little but I hate it I take extreme care of these barrels and don't understand where it came from if it matters is a round groove barrel

[Top Jaw]

I’d second the maroon scotch brite cut patches, and some scrubbing. You will probably have to drop down one jag size to accommodate the thickness. 

[smylee grouch]

Try cleaning without the dish soap , and if your using hot water switch to room temp water and WD 40 after bore is dry to see if that works.

[AZshot]

To me, it's a "what you don't know won't hurt you" situation.  I've never owned a borescope, never used one.  I've been very active in all shooting sports my whole life, about 50 years at this point. 

If you are looking at the spots, and have to stop them, just try scrubbing harder in those areas.  Maybe use s nylon bristle brush, or some Tow.  Use some CLP oil and see if it can be turned to black rust.

[Pukka Bundook]

What AZ or Daryl say.

I don't like Scotchbrite much as it scours the surface of the metal more than I like. The Solvol Autosol leaves a Very smooth surface, that is hard for rust to get a hold of.

[alacran]

I have to agree with AZ shot. I clean as I always have. I never use WD 40 or soap. Last thing I do before oiling, is run 91% rubbing alcohol down the barrel.
It always brings out some more blackness. I dry the barrel with patches until they are hard to pull out.
If the rifle shoots the same as it did before you noticed these blemishes. I would not worry about it.

[Waksupi]

The WD-40 could be turning to varnish. That has to be wiped out completely before oiling the bore.

[Daryl]

Soaps are not needed. Using ANY soap is not being good to your barrel. It is not needed, even if you use
an oil or grease lube.
After drying my barrels & locks are FLUSHED with WD40. Then that the WD40 pumped out the vent or nipple seat with a fresh cleaning patch,
several strokes, then the barrel and lock are wiped down and returned to the stock.
Been doing it this way since 1975 or 76.
NO rust, ever.

[hortonstn]

Some of the guys I shoot with use windex to clean, the original with ammonia sounds wrong to me
Then oil I thought ammonia was bad!!

[Daryl]

Ammonia will react with some steels,(& some more than others) which is why smokeless powder and copper solvents with ammonia in them,
have a time limit for being in the bore. That time limit is 15min. for most of those solvents. Copper solvents without ammonia usually do not
work very well in my experience. Been using copper solvents since 1968.

[Hawg]

The WD-40 could be turning to varnish. That has to be wiped out completely before oiling the bore.

WD-40 does not turn into varnish, that's internet lore. All my dad used to clean his guns was WD-40. I got them after he died and there was no rust or varnish. They were just dry. Nothing a little oil didn't fix. If you're getting varnish some other oil caused it.

[Scota4570]

IF you have a rough rusty bore it will foul up very quickly.  You will have to clean between shots.  That means cleaner in the bore.  That causes misfires.  I do not have the patience for that.  Make it nice and shiny and have more fun shooting. 

[Darkhorse]

Can you feel those rust spots with a cleaning patch? It will feel like a rough spot. If not it might not be rust at all. What patch lube are you using?

[hortonstn]

Patch lube is machine oil/Mr kleen/water this is used by many benchrest shooters at Friendship