pitted bores

[SKS Ray]

I posted this on another forum but didn't get a straight answer so I figured i'd ask here in case anyone had an opinion.
I recently picked up an old Argentine Mauser that has a fairly pitted bore. Nothing to the point that accuracy looks like it'd be a problem because it still has great rifling right up to a nice sharp crown, it just looks a little crusty in the grooves. I used a bronze brush and some Break Free and scrubbed it with about 20 passes. It cleaned up a little but its not as clean as i'd like it to be. Now i've heard of people using a shoot-clean method where you can take a rifle with a sewer pipe bore and after putting 50 or so rounds through it, then perform a standard cleaning, and the bore comes out pretty nice. I've never had to try it but i'm guessing fouling fills in any pits and smooths out the imperfections to give it a cleaner look and function.
Has anyone used this method? And if so do you think using corrosive ammo to do it is a bad idea? I don't want corrosive salt deposits filling up the bad areas of my bore, but its all I have for this rifle. I know all about the clean up for shooting corrosive ammo, I do it most every time using old milsurp ammo with hot soapy water when I get home that night from shooting, or with window cleaner at the range before I pack up. I'm just not sure if fouling a barrel's imperfections with corrosive ammo is a good idea, or if the copper will do it w/out leaving deposits where I can't get them afterwards.

 

[Nickle]

I have 3 Mosin Nagants. Two of them (the Finn's) have bores that look like the inside of a sewer pipe. The M24 won't clean up anywhere near shiny, and I've shot it a fair amount. It does shoot fairly accurately, though.

I think the shoot it clean method is pure BS. The problem you have is pitting. That is metal missing. The only cure for it is to rebore or replace the barrel. PERIOD.

I suggest cleaning it best you can, then turn your mind off to the pitting. There are no "magic fixes" for it.

 

[Scrivener]

You could try JB Bore Paste. It won't make the pits go away - nothing will - but it will clean all the crud IN the pits out of them, which is the next best thing.

 

[jacobtowne]

I have a couple of rifles with pitted bores. One, a SMLE No. 1 Mk. III made at BSA in 1927, has actually come pretty clean after several hundred rounds and many cleanings. The bore looks fairly smooth now, but as Nickle points out, you can't eliminate rust pits.
As for cleaning up after shooting corrosive-primed ammunition, you do not need to use hot, soapy water.

Corrosive primers contain potassium chlorate (KClO3). After firing, this chemical leaves behind potassium chloride (KCl) crystals. Potassium chloride has properties almost identical to sodium chloride - table salt (NaCl). In fact, potassium chloride is used as a salt substitute for people on low-sodium diets.
Both of these chemicals are hygroscopic - they absorb moisture from the air, creating tiny droplets of salt water. And we know what salt water does to steel.
Cleaning these salts from a bore requires a water-based cleaner, since they are water soluble.
People have used plain water, Windex, water with a drop of dish soap, and black powder solvent successfully. The point is to never clean with a modern nitro solvent as a first cleaner, since most of these contain oil.
Many years ago, before WWII, Army Ordnance discovered that ammonia dope was the most effective way to dissolve and neutralize these salts.
I use regular household ammonia diluted with two to four parts water.
Moisten two patches - not dripping wet. Run one patch through the bore. Wait ten minutes. Repeat.
Moisten two patches with plain water and run them through the bore several times.
Dry the bore with a dry patch.
Set the rifle against a wall muzzle up for while to insure that the bore dries.
Proceed with regular nitro solvent and brush.
JT

 

[Nickle]

When I'm using corrosive ammo, I make sure and have a spray bottle of Windex (or generic equivalent) with me. I squirt a generous amount through the barrel after I'm done shooting for the day, and clean at home that evening. It helps.

 

[SKS Ray]

Thanks for the answers and replies. I just have one question now... what is it about shooting a rifle with a crusty bore that seems to smooth out the rough areas? Jacobtowne mentioned an Enfield that he had better results with cleaning after he shot it several times. What kind of process is going on there, are the bullets basically scrubbing out the crud, or is the fouling filling in pits?

 

[Nickle]

I would say that the bullets are scraping off the surface rust inside the bore. I should mention that I tried several different bore cleaners including Iosso paste on the M24.

 

[Adam_MA]

Also, after cleaning, and shooting a bunch of ammo the copper fouling will start to fill in the pitted areas, making it look better.

Adam

 

[SKS Ray]

I was worried that the corrosive agents would get inside where I couldn't clean because copper fouling would start burying them in as I shot the rifle.
One thing I learned from people who shoot match grade 22 barrels is that scrubbing to remove fouling decreases accuracy because the fouling has fulled in imperfections in the bore. Thats why most recomend a bore snake or just using wet then dry patches.
I think for this rifle I might do a cleaning method i've heard some folks mention where they shoot a magazine full of rounds, clean lightly with a wet patch, then dry, shoot more rounds, clean again, etc. untill the bore is what they refer to as "seasoned".

 

[Nickle]

Copper fouling from jacketed bullets will hurt accuracy. Ask any High Power or Bench Rest shooter.

 

[SKS Ray]

Jacketed ammo in high power rifles I agree will reduce accuracy. I should have mentioned that the its shooting lead nose 22LR ammo through match grade barrels that i've heard a lot of people say they don't scrub there bores clean.

 

[sheriff dudley]

mill4me all of those answers to your questions are good ones! and i have
another to furthur confuse you!! (WEASLE PISS) is use this for all of my corrosive issues, muzzle loaders, especialy my flint guns that i cant
remove from there stocks,B.P.C. rifles,and of corse millsurps 8mm,s
7mm,s .762x54s and anything that i suspect is corrosive!!! the formula
is 1/3 Murphy,s oil soap, 1/3 rubbing alcahol, 1/3 hydrogen peroxide,!!!
thats it, believe me i have tried alot of things before this stuff but this is
all i have used since someone gave the formula!!

Take Care Sheriff Dudley S.A.S.S. 17925

 

[NEtracker]

JB Bore Paste works wonders in some of my barrels.
Pitting does make it more work to cleanup after a session...