Dark Bore on Yugo M48- Do I have to replace the barrel?

[offthepaper]

I have a Yugo M48 that has a dark bore, rest of the rifle looks pretty nice though. I have'nt shot it yet, so I don't really know the accuracy of it. What exactly causes a bore to turn dark, and does it mean the barrel will have to be replaced before it can become a decent shooter? Is it possible to clean/brighten the bore with solvents or it a hopeless cause?
As always...thanks in adavance.

 

[DMK]

Try shooting it before you do anything. Some rifles with dark bores are still very good shooters. Sight it in and get some careful five round groups on paper at 100 or 200 yards. Use a few different types off ammo (a lot of my surplus rifles favor ammo from one country or certain bullet weights). Take the targets home, and compare the groups. Get an idea of what you have there before you go off trying to fix something that's not broken.

What exactly causes a bore to turn dark

A dark bore is pits in the metal of the bore. This is cause by rust, which in turn is caused by improper cleaning, usually after shooting corrosive ammo. It is NOT caused by a lot of shooting. In fact, many surplus rifles with dark bores have very low rounds through them (ie. they are NOT worn out).

Is it possible to clean/brighten the bore

No, not really. Think about a pitted bore for a moment. You can't fill in the holes by cleaning, you can only remove the metal around the holes. You definitely don't want to do that. The black stuff you see on the patches when you clean it is stuff that was stuck in the holes.

Many pitted bores still have sharp lands and grooves. They also may still have good throats and good crowns at the muzzle. That's good for accuracy. By overcleaning, trying to "shine" the bore up, you risk wearing down the lands and wearing out the crown.

The best thing to do is use a chemical foam cleaner. Follow the directions (most say let it sit overnight). Use the least amount of scrubbing with a brush or the least use of abrasive cleaners as possible. Oil it good. Now shoot it with some copper jacketed ammo. Do not use a copper cutter when cleaning. Let the copper fouling fill in the pits.

When shooting corrosive ammo, always flush the bore with soap and water (warm or hot if possible). A drop of dish soap in a half a cup of water is good. Windex or any generic window cleaner will work too in a pinch. Soak a patch with the solution and mop out the bore. Dry patch immediately. Repeat a couple times. Now clean as usual.

Good luck!

 

[Jackal]

I am not meaning this in a stupid way... Have you cleaned the barrel? If it is a cosmo soaked M48, the barrel will be dark. Hit the bore with a barrage of solvents, brushes and patches and see if it cleans up. I once had a Mosin M44 that appeared to have a badly pitted bore. I got it for $25 just for that reason. I got it home, cleaned the piss out of it and guess what? It's no longer a sewer pipe and only has 1 tiny patch of light pitting. It also a great shooter.

 

[MilsurpShooter]

Outers foaming bore cleaner. Plug the muzzle and leave it soaking muzzle down for 20-40 minutes. Clean as normal. See what happens and go from there. Did that with an old .22 I found, thought the bore was worthless, turns out it was just full of dust and is mirror bright now

 

[Plink]

Many times a dark bore will shoot just fine. Because of the roughness, they can foul more though. Clean it thoroughly then go shoot it. If it's a good shooter, some lapping will help clean the bore up.

 

[atomchaser]

If it shoots well, don't worry about it. I have a K-98 that shoots great but has a dark bore. Just be sure that you water/soap/ammonia cleaning at the range after shooting corrosive ammo. I also run a dry patch followed by an oily patch at the range since I live in a very humid environment. I do a regular cleaning once I get home.

If it really bothers you, just get another one with a bright barrel.

 

[RockyMtnTactical]

The biggest question IMO is, "what have you tried so far?"

 

[Coronach]

Yeah, as was said:

1. Don't Panic. A good first step in any problem-solving process.

2. Clean the bore, and see how good you can get it with a little bit of normal effort. Emphasis on the normal...if it is pitted, you can wear your arm out working the cleaning rod and you'll only make it worse. Just run some patches through it and see what it looks like.

3. Try shooting it. You'd be surprised what it might be able to do. Just becuase it is pitted does not mean that it cannot be accurate. It only means that it will be more of a PITA to clean.

4. MAKE SURE YOU CLEAN IT. Most of the ammo for 8mm is corrosive. Not only is this how the bore came to be pitted, it is also what will cause it to get worse. Clean that bore after every range visit.

If, after all of that, it still is minute-of-barn accurate, you can contemplate a rebarrel. But I would not worry about it until I knew what it could do as-is.

Mike

 

[DMK]

Just because it is pitted does not mean that it cannot be accurate. It only means that it will be more of a PITA to clean.

That is an excellent point! You'll never get white patches out of it, but it may surprise you in how good it shoots.

Even if it doesn't shoot well, don't automatically assume it's because of the dark bore. Check the other stuff like: see if there's a ding on the crown, check the stock fit, make sure the action screws aren't too tight or too loose, try different ammo, check headspace, make sure the sights aren't loose, try loosening (or tightening) the barrel bands, etc.