Dark Bore?

SP45

Hey,
I was looking at a used gun recently, it was a 1941 Mauser according to the numbers and markings. The gun was is pretty nice condition but when I put a bore light to the chamber and looked at the barrel it was dark. It had good rifling but it was dark. Does this merely indicate fouling or is this a shot out barrel? Thanks

SP45

Anyone know of a way to clean a dark bore without further eroding the bore.

nmyers

It's difficult to know what a "dark bore" means. Does it just have a lot of burned powder & lead in it, or is it full of pits from corrosive primers & moisture? Gunsmiths use a fiber optic bore scope to get a good look at the bore.

If it's been cleaned with solvent & a brass brush, sometimes an electrolytic solution with chemicals & electric current will sometimes clean up a badly leaded bore; again, usually only gunsmiths have these.

Frosting (light corrosion) can sometimes be removed with an abrasive, such as J-B Bore Paste.

But, bad pitting can't be fixed; what you are seeing are areas where the steel is gone, rusted & corroded away. Nothing can fix that.

Neal

navc130

On the assumption you are dealing with a military gun that is corroded from corrosive ammo, there are two methods I have used.
(1) Mechanically - a stainless steel bore brush or a bronze brush wrapped with steel wool. Use a solvent with the brush - mineral spirits, light oil, penetrating oil.
(2) Chemically - a mild acid solution. Plug the bore and fill with the acid solution; let set for 12 hours. Use a bore brush to scrub out. Clean the bore with water. Acids also cause rust. May have to be repeated more than once. Protect the bluing with grease or plastic wrap.

charliemeyer007

A Loverin style lead bullet oversized and the grease groves filled with toothpaste or JB bore paste, just shoot them.

You might specify the weapon.

I'd start with a wire brush and a good solvent like Shooters choice then a patch followed by inspection. Once or twice for a week.

Rubber cork the chamber, fill the bore and let it soak for a few days.

Some rifles still shoot "good" with a dark bore.

KAMsales

Been using this stuff for years, has cleaned up hundreds of sewer pipe barrels. Its the only gun cleaner we carry here

http://kingarmory.com/Blue-Wonder-Gun-Cleaner_p_109.html

kimi

A product that I learned about on this forum years ago is Kroil. I used it on an old .22 that I thought was badly pitted and leaded up, by plugging the muzzle end with a cork stopper, filling it with Kroil, and letting it soak for about a week. I then emptied it and ran a bore brush wrapped with copper strands from a Chore Boy pad and dipped in Hoppes No. 9, followed with running patches through until they came out clean. It worked wonders and I am now repeating the process in hopes that it will continue to clean up and not show any pitting at all.

mmppres

fill bore with kriol or ballistal an keep brushing every few days it will clean up most dark mores

tsr1965

quote:I'd start with a wire brush and a good solvent like Shooters choice then a patch followed by inspection. Once or twice for a week.

Rubber cork the chamber, fill the bore and let it soak for a few days.


DO NOT EVER let the bore soak, filled or wiped on with Shooters Choice(or any other ammonia based solvent), more than 10-15 minutes. It can, and will ruin a good bore, let alone an iffy one.

Soak/fill with Kano Kroil, and wire brush until clean. Repeat as needed.

abcguns2

Clean : Kroil ( soak ) : J B Borebrite !!!!!!!

RCrosby

And after cleaning with all of the above, you may still have a dark bore BUT it may shoot quite nicely. Will need to be cleaned more often, but accuracy may be fine. Find out before taking more drastic
(i.e. expensive) measures.

v35

Fill the bore with a sleeve reamer and resleeve the barrel.
It may shoot very well as is but you'll have to scrub it for every shooting session.
No free lunch, you've a bad barrel.