What problems to expect with a pitted bore?

[The Freeholder]

I have a Dutch Mannlicher that I got from my Dad. It's a WWII war trophy, all matching serial numbers.

I finally took it out to shoot, and when I started cleaning it, the goo coming out of the barrel was incredible. So I kept cleaning. And cleaning and cleaning and cleaning. Eventually I got all the crud out...

and the bore seems to be pitted pretty badly. I don't have a borescope, but it looks like ther is some pitting on the lands, and som pitting in the grooves where they meet the grooves (like it is in that angle made by the land meeting the groove).

I guess no one ever cleaned it properly, if at all.

The gun shot pretty well when I was shooting it--I was reliably hitting a 12" steel at 100 yards unsupported. My question is what effects can I expect serious pitting to have, especially on accuracy? I don't mind if the gun isn't MOA--it's a military gun, and I don't expect such things from them.

Also, will I cause further harm by shooting and cleaning? I was pretty aggressive this time--lots of bronze brushing. If I really have gotten it all out, I expect I won't have to be so aggressive in the future.

Any wisdom will be welcome, because I'm way out of my area on this one.

 

[The Real Hawkeye]

I have a Dutch Mannlicher that I got from my Dad. It's a WWII war trophy, all matching serial numbers.

I finally took it out to shoot, and when I started cleaning it, the goo coming out of the barrel was incredible. So I kept cleaning. And cleaning and cleaning and cleaning. Eventually I got all the crud out...

and the bore seems to be pitted pretty badly. I don't have a borescope, but it looks like ther is some pitting on the lands, and som pitting in the grooves where they meet the grooves (like it is in that angle made by the land meeting the groove).

I guess no one ever cleaned it properly, if at all.

The gun shot pretty well when I was shooting it--I was reliably hitting a 12" steel at 100 yards unsupported. My question is what effects can I expect serious pitting to have, especially on accuracy? I don't mind if the gun isn't MOA--it's a military gun, and I don't expect such things from them.

Also, will I cause further harm by shooting and cleaning? I was pretty aggressive this time--lots of bronze brushing. If I really have gotten it all out, I expect I won't have to be so aggressive in the future.

Any wisdom will be welcome, because I'm way out of my area on this one.

Many badly pitted bores will still shoot very well. The problem is that they get dirty faster, and are harder to clean.

 

[Roudy]

Freeholder,

Last week I "discovered" a really neat bore cleaning product that many people have known about all along. Foaming bore cleaner. This is really neat stuff and not too pricy. You just squirt it into your bore and it foams up to fill the bore. The neatest part is that you can watch the white foam change colors, at the muzzle, to blue (copper0 and/or brown (dirt & crude).

You might want to try it. Won't fill in the pits, but I think it will get the bore clean.

Roudy

 

[DnPRK]

1. Take your cleaning stuff to the range.
2. Shoot 5 shots as fast as you can cycle the bolt, then clean immediately while it is still hot.
3. Repeat 3 more times for a total of 20 shots and 4 cleanings.
4. After this regimen, the bore will be as clean as it will ever get. With any luck, there might be some shine in there after you're done.

 

[BevrFevr]

the reason for the pitting may be

from corrosive ammo. Lots and lots of old military surplus guns have this problem.

You must nuetralize this with ammonia. Windex with ammonia or your own urine can do the trick. Hell even plain soap and water.

If you have cleaned the corrosvie goo out you may want to throw out any brushes you used and start fresh.

I bought some ammo I did not know was corrosive and shot through my tokarev. Damn thing rusted up like an old sewer pipe in no time. still shot well though.