Help: Is this a carbon ring?

mrjashu · May 3, 2020

Hello folks,
I'm far from a gunsmith. I'm just a guy that like to shoot and reload, so I was hoping to lean on some of the vast experience of this forum.

A buddy gave me an old hunting rifle to work on his reloads for him. He had been running the same load for years but it suddenly stopped shooting good. Also the velocity went through the roof. He thought maybe powder lot or bullet lot changes might have been the problem. I shot it a little bit with some very light loads (according to the book) and pressure was bad right from the start. I did a light cleaning on the rifle (patches only no brushing) and thought maybe I'd try out my cheap Amazon endoscope to see if I could see anything.
I know the pictures are low quality but is it enough to determine the issue? I'm seeing a black ring in the throat area, is that the dreaded carbon ring? Could that be what's causing the pressure spikes?
I'm also curious about the black streaks on the lands, is that fire cracking? Any help interpreting these (admittedly low quality) picture would be appreciated.
Thanks in advance.

Frog4aday · May 17, 2020

The resolution of the images isn't good enough for me to venture an educated guess, but based on what you wrote, it seems like a really thorough cleaning is in order. Carbon is an itch with a B to get out, and most say that C4 Bore Tech carbon remover is a good product for routine cleaning, but once the carbon gets so thick and embedded, some BROWNELLS J-B NON-EMBEDDING BORE CLEANING COMPOUND with a lot of scrubbing, scrubbing and more scrubbing is going to be needed to finally get it out. Did I mention it's going to take a lot of elbow grease and time to get the carbon truly out? This isn't going to be a quicky job.

Once the carbon is out of the barrel and throat, it's time to tackle any copper build-up and WIPE OUT (left over night) or Bore Tech Cu+2 Copper Remover seem to do the trick. Another great product for copper is Sweet's 7.62 Bore Cleaning Solvent, but you can't leave it in the bore for more than 15 minutes.

I'm pretty certain once the carbon and copper are gone, the gun will shoot fine again and the pressure problems will be a thing of the past. It's just going to take time and work. Thankfully your bore scope will help you track how you are doing on that carbon in the throat/leade area. Many a person has written how they THOUGHT they were cleaning their guns really well only to get that Tesalong bore scope off Amazon and see how much 'stuff' was still in the barrel!

mrjashu · May 17, 2020

Thanks for that, I'm in the process of doing just what you suggest. Hopefully that will take care of things.
FWIW I started a different thread over here with better pictures