Can This No. 4 Barrel Be Saved? (Or Is It Me...)

[tj214]

So. A bunch of years ago I bought a No. 4 Mk. 2 because the numbers matched, but it sat in the back of the safe ever since. Pulled it out this week to clean it up and maybe shoot it a bit over the Christmas-New Year break. (Yup, I should have cleaned it up when I first bought it but was extremely busy at the time (excuses, excuses) and anyway that's water over the dam).

The exterior actually looks to be in good-excellent shape. The bore is a different story.

Based on advice from somebody on this site I bought a bottle of Patch-Out liquid because it seemed possible the barrel could have some copper fouling; in any case better safe than sorry.

Day #1: Ran a wet patch through and it came out bright darkish blue. Kept running patches through (about 15) and although decreasingly bright were still distinctly blue. Switched to nylon bore brush; back and forth five times, then followed with a patch wet with Patch-Out. O.M.G. The patch was absolutely black--almost muddy. Not good.

Fifteen more wet patches through and although no longer muddy, still had some blue color. Let's try the nylon brush again...EXACTLY the same result as before: muddy black patch with blue at the edges. This is the place for a well-known military technical acronym: C. R. A. P.

Repeat cycle three more times; same results each time.

Night #1: Run patch well soaked with Patch-Out and let it soak overnight (about nine hours).

Day #2: Replay of Day #1, except in between running wet patches 1) ran the nylon brush through five times each way--still got a muddy black/blue wet patch out right after. 2) After another iteration of wet patches, switched to a brass brush--got a REALLY muddy black wet patch out right after. Repeated wet patches--brass brush routine twice more, with EXACTLY the same result each time: muddy black wet patch right after.

Night #2: Well-soaked patch through to soak overnight again.

Day #3: Exact repeat of Day #2, except used only brass brush each time in between wet patches.

Night #3: TWO well-soaked patches to soak for 24 hours.

Night #4: 24 hours after last wetting with Patch-Out, ZERO change from the very first time I ran a patch through this barrel. Bright blue if Patch-Out only, and muddy black with dark blue edges after brass brush runs. I've now used almost half a bottle of Patch-Out and way over a hundred patches, so I'm out of ideas.

I don't have a borescope, and don't see any point posting pics of the patches or the towels used to wipe down the cleaning rod after each pass (although I can if you'll think they'll help).

I acknowledge the distinct possibility of operator error, so am I doing something silly here? I've cleaned a reasonable number of rifle and pistol barrels over the decades, and even the range rifles they gave us pilots on range day were not even close to this dirty.

You guys are the Subject Matter Experts, so I'm all ears (actually, eyes).

[browningautorifle]

Sounds like it's still filthy. Even if the bore is completely ratholed out, once you get the crap out it'll be clean. Just done for. I had a Winchester I could clean until it had shine and the next day it would come through dirty again. Once it was clean it would show clean. Once it sweats out again you repeat.

[Low & Slow]

Yep. Bores, especially when pitted, can hold a lot of nastiness. Layer after layer of copper and powder fouling, then rust. Hopefully you're not at .35 cal when mostly clear.

[Singer B]

I have seen several others post that after the first cleaning, go out and shoot as that may actually remove or loosen some of that old nasty fouling. That has worked for me in the past and it can't hurt the gun either.

[Daan Kemp]

Time to go and shoot it. Twenty to thirty rounds should remove a lot of rubbish.

[RobD]

i could be wrong, but it sounds like there could be lead deposits in your rifling. Could that fit?

[browningautorifle]

lead deposits

This...

[Brian Dick]

If you want to see if your barrel is still in spec. Go to APEX gun parts and buy the correct gauges to check it with. I've cleaned many LE barrels over the years and the majority will be just as yours unless they've never seen service. Heavily fouled and with brown/black fouling-rust. If the rifling is still decent and in spec, you'll be surprised that they will still perform on the range. This is the simplified WW2 specification and appropriate gauges.

.307 plug - must not enter the muzzle more than .25"
.310 plug - must not neter the breech more than .25"
.301 plug - must run through the barrel with no resistance.

Everyone who worries about their barrels in LE rifles should have these gauges in their tool kit. They will tell you pdq if your barrel is worth saving or scrap.

[Bruce_in_Oz]

There is a very good reason that actual military operators of these items were keen on BOILING WATER, generously funneled down the barrel, preferably as soon as possible after firing.

Only a couple of caveats:

1. Using the correct funnel in the correct way and NEVER letting the hot water get into the woodwork, unless you want to get really adventurous and strip off the fore-end to dry it out and re-grease the metalwork.

2. Dry the bore with a CLEAN patch as soon as the boiling water stops coming out of the muzzle "discoloured..

3, IMMEDIATELY swab some oil through the bore while the barrel is still hot.

4. A couple of days later, do another "conventional" clean. This may show up a bit more jacket streaks and some dark propellant residue. This why we do a "follow-up" clean.

Yes, "modern" commercial ammo uses "non-corrosive" primers, BUT, slow corrosion can start, especially if you live in a humid part of the world, like coastal Florida or Queensland, etc.

The "old-timers / military users were intimately familiar with the evil residues from the issue ammo; (mostly hideously corrosive salts from the residue of the primer.

Once the rifling is "pitted", it will scrape off a lot more bullet-jacket material and this will also seal in little pockets of that corrosive residue.

[Peter Laidler]

I agree with all of the above. The barrel is only scrap when it is thoroughly clean and scrap. Even then, be advised that because a barrel looks like a sewer pipe doesn't mean that it won't be accurate. No4T's were a good example of this. Occasionally you'd get one that looked like a sewer pipe that shot absolutelt perfectly and accurately, So much so, thee sniper (who always had the last word, as his riifle was a personal issue to him) would tell you - in words that you would quickly understand - that it was perfect. While others would be all over the place and fail even the most basic accuracy test

When you start to scrub the barrel, make sure that you're only taking the crap out and not the bore out! We used to use a pink coloured tablet mixed with water (?) called KNS tablets - for Cupro-Nickel solvent. Any old Armourers out there remember using KNS tablets? I didn't see them in Oz but we did have them in NZ

L96's were a good example of where a new barrel could shoot worse that a new barrel. Don't ask me why. Some say a change of manufacturers from XX to XXXXX XXXXXXX. But even that assumption was never proven.