Buildup of Copper

[MW204]

Here is another issue that I have discovered, it looks like a carbon ring about halfway down the barrel and it's right in there where the really heavy copper buildup is. Also here's a pic of the copper buildup after a little cleaning.

 

[MW204]

Here's a video of the barrel after I cleaned the first layer of carbon out of it and let it soak all night with Hoppe's foam. As you can see there is still some carbon on top of the copper, but that isn't a problem at this time. The heavy copper is midway down the barrel and is about 5-8" long.

 

[vancewalker007]

Not really attempting to pattern it right now because I'm shooting factory ammo I was given to use to break it in but it shoots about a 4" group.

Well you may have a bigger problem than copper. But, factory ammo can be pretty bad in a lot of cases.

 

[MW204]

Well you may have a bigger problem than copper. But, factory ammo can be pretty bad in a lot of cases.

I think the barrel is defective and I'm sending it back to Shilen next week. When I shoot a 5 string the entire barrel is covered in copper, the first 10" or so is not that hard to clean nor is the last 6-10", but in the middle, it's tough to get the copper out. I'm still working on it from the last 5 shots from last evening.
Shilen asked me to send it to them dirty so they can see exactly where it starts to copper up bad so when I get it clean again I'll shoot it a few times and let them work on cleaning it.

 

[vancewalker007]

I think the barrel is defective and I'm sending it back to Shilen next week. When I shoot a 5 string the entire barrel is covered in copper, the first 10" or so is not that hard to clean nor is the last 6-10", but in the middle, it's tough to get the copper out. I'm still working on it from the last 5 shots from last evening.
Shilen asked me to send it to them dirty so they can see exactly where it starts to copper up bad so when I get it clean again I'll shoot it a few times and let them work on cleaning it.

Sounds like they are being very responsive. They should make it right. I had a Shipment years ago in 7mm STW that was great, but sometimes I'm sure everyone has a bad one slip out. That being said copper fouling in perfectly normal in fast stepping cartridges and should not cause 5inch groups. Seems like there is consistent size issue with the bore, which could cause some weird oscillation in a bullet.

Good luck.