Buildup of Copper

MW204

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612
Location
North Texas
My son-in-law bought a new air gauged barrel from Shilen in a 300 WSM, threaded and chambered. I set the headspace on it and he's fired it 3 times. Since then I bought a borescope and boy did his barrel have a lot of copper buildup in it. I can't believe I didn't take a pic then, but he's been extremely busy at work, with no one willing to work, so I decided to clean his rifle for him.
I gave the rifle what I would call a good cleaning before using the bore scope again. The barrel cleaned up pretty good imo, but there were 3 spots that still had copper in it and it took a lot of cleaning to get the remaining copper out of it.
I shot the rifle 2 times and ran the borescope again and imo it had a lot of copper in it just after 2 shots, plus no matter what cleaning process I used it left a lot of white spots, which I'm guessing is part of the patch that is being pulled off.
My questions are.
1. does a new barrel actually copper up this fast?
2. with those 3 spots having copper buildup in them does that mean the barrel has a void in the rifling?
3. are the white spots patch material that is being ripped off by the rifling?

I'll try to line the pics up as I took them and then the videos. (working on the videos)
 

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You need a mirror so you can look at the spots more precisely.
I have a barrel, 4 groove custom, that coppers quite a lot but shoots excellent.
Here's a pic or two.
Cheers.
 

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You need a mirror so you can look at the spots more precisely.
I have a barrel, 4 groove custom, that coppers quite a lot but shoots excellent.
Here's a pic or two.
Cheers.
I do have a mirror attachment and I'll go out this morning and take a look and once I have it clean again I'll look closely at the white patches to see if I can see a nick where the patch is at.
I wish I could attach the video, but so far no luck. It would show the barrel after 2 shots really well, the inside is completely covered after those 2 shots. The white spots have to be patch material that is being pulled off by nicks and dings. He bought a Match barrel but it is not lapped so maybe he needs to do a little polishing to take out the sharp edges.
The main thing that bothers me is those streaks of copper in the pics that took so long to get out of the barrel. To me, those places are void spots and it may not make any difference but then again it might.
See what happens when we get new toys we find new issues or we think we find new issues. I like the camera because I followed my usual routine of cleaning a barrel and even after Sweet it did not show any purple on the patch but those short streaks of copper were still in the barrel and I never would have guessed that.
 
You need a mirror so you can look at the spots more precisely.
I have a barrel, 4 groove custom, that coppers quite a lot but shoots excellent.
Here's a pic or two.
Cheers.
The number 3 pic is what I found after my normal cleaning and it took a lot to get that copper out. There were 2 other small places of copper like that but not as long. I used Hoppe's foam and that is what got the last pieces of copper out. I foamed the barrel, went to Church, and cleaned the barrel when I got back and it was gone.
 
Barrels have to be "seasoned", just like race engines, it takes time, and in this case, bullets down range for things to settle.
Run the barrel in with 100 rounds before making judgement on the fouling issue.
A rough barrel WILL smooth out with time and may shoot great just as, give it plenty of love for that 100 rounds and you may have a great shooter for a long time to come.

Cheers.
 
My son-in-law bought a new air gauged barrel from Shilen in a 300 WSM, threaded and chambered. I set the headspace on it and he's fired it 3 times. Since then I bought a borescope and boy did his barrel have a lot of copper buildup in it. I can't believe I didn't take a pic then, but he's been extremely busy at work, with no one willing to work, so I decided to clean his rifle for him.
I gave the rifle what I would call a good cleaning before using the bore scope again. The barrel cleaned up pretty good imo, but there were 3 spots that still had copper in it and it took a lot of cleaning to get the remaining copper out of it.
I shot the rifle 2 times and ran the borescope again and imo it had a lot of copper in it just after 2 shots, plus no matter what cleaning process I used it left a lot of white spots, which I'm guessing is part of the patch that is being pulled off.
My questions are.
1. does a new barrel actually copper up this fast?
2. with those 3 spots having copper buildup in them does that mean the barrel has a void in the rifling?
3. are the white spots patch material that is being ripped off by the rifling?

I'll try to line the pics up as I took them and then the videos. (working on the videos)
Is the rifle shooting poorly?
 
Sounds like a rough barrel in need of lapping. I have seen a few of thses that gave up accuracy quickly, like after 10-15 rounds. A solvent containing Ethanolamine will disolve copper. An indication of ethanolamine reaction with copper may be seen by green-blue stains on patches that have been soaked with ethanolamine with various brass jags or other items contacting the soaked patches. Black crud of unspecified origin will also be attacked. Motor oil (of the detergent type) is another surfacant and applied with a brush. is useful for floating away crud including loose copper.

Ethanolamine will not corrode or rust barrel steel. Corrosion resistance of stainless is due to the continual formation of protective barrier of chrome oxide.

Progressive copper fouling will really adversely affect accuracy. Imaginine shooting the last 20 at 600 yards for score with a rough barrel that has been subjected to 30 or more previous rounds. Bullets, primers, & powder are pricy.

My sugggestion is to lap the barrel. Use a nylon or bronze brush, dip the brush in vsalve grinsing compund and work it thru the barrel. Push the brush completely thru the barrel before reversing the stroke. Load the brush with vslve grinding compound every 20 stokes for a total of 100. Upon completion a re=crowning the muzzle would be a good idea.
 
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Is the rifle shooting poorly?
At this time all we're doing is loading up some least used powder, salvaged primers I pulled/sealed, and bullets removed from some brass I gave away. So at this point IDK but we are starting to group even this stuff to see if the 2" group gets smaller. I set up the chrono today to see what the velocity and of course the 9v battery was dead.
 
Barrels have to be "seasoned", just like race engines, it takes time, and in this case, bullets down range for things to settle.
Run the barrel in with 100 rounds before making judgement on the fouling issue.
A rough barrel WILL smooth out with time and may shoot great just as, give it plenty of love for that 100 rounds and you may have a great shooter for a long time to come.

Cheers.
That's the plan
Sounds like a rough barrel in need of lapping. I have seen a few of thses that gave up accuracy quickly, like after 10-15 rounds. A solvent containing Ethanolamine will disolve copper. An indication of ethanolamine reaction with copper may be seen by green-blue stains on patches that have been soaked with ethanolamine with various brass jags or other items contacting the soaked patches. Black crud of unspecified origin will also be attacked. Motor oil (of the detergent type) is another surfacant and applied with a brush. is useful for floating away crud including loose copper.

Ethanolamine will not corrode or rust barrel steel. Corrosion resistance of stainless is due to formation of chrome oxide.

Progressive copper fouling will really adversely affect accuracy. Imaginine shooting the last 20 at 600 yards for score with a rough barrel that has been subjected to 30 or more previous rounds. Bullets, primers, & powder are pricy.

My sugggestion is to lap the barrel. Use a nylon or bronze brush, dip the brush in vsalve grinsing compund and work it thru the barrel. Push the brush completely thru the barrel before reversing the stroke. Load the brush with vslve grinding compound every 20 stokes for a total of 100. Upon completion a re=crowning the muzzle would be a good idea.
I have done this on a couple of my barrels and it worked great, no bore scope then though, but this is a new barrel with a guarantee and the minute I put valve compound in it the warranty will be void, but I did tell my son in law about it today.
 
You need a mirror so you can look at the spots more precisely.
I have a barrel, 4 groove custom, that coppers quite a lot but shoots excellent.
Here's a pic or two.
Cheers.
I looked at the bore with the side mirror this morning and it looked pretty much like your pics.
I contacted Shilen and they said I can send the barrel back so they can inspect it and a valued member on this site said that's why he'd do. I'm going to run 50 rds through it to see what happens. I was going to use the chrony today but the battery was dead so I'll pick up some tomorrow and give it a try to see what it does with the remaining 40 rounds. After that, if it's improving then I'll try another 50 rds and see what happens.
 
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