Carbon ring? Removal?

I noticed at my last range session that known safe and accurate loads in my 7saum started to show pressure signs (light ejector mark), recoil was heavier and accuracy wasent the same. I went home and cleaned barrel very good. Went back out today and the problem got worse. I shot 8 rounds and stopped. Recoil was very heavy, ejector swipe was heavier and primer was cratering. I also noticed that the case mouth appeared to have a look of being slightly beveled inward. I did some research and all signs lead to a carbon ring. I have never had a problem with a carbon ring before and don't own a bore scope so can't confirm it visually. Does this sound like a carbon ring to you guys, and if so, how would you go about removing it? I read 20 different procedures online and I really would rather not run abrasives in the barrel if it can be avoided? Is this a trial and error type thing if I don't have a bore scope to visually confirm I have removed it? Any insight would be appreciated from those with experience.

By the way, I'm using H1000 which is pretty dirty.

Might be the case necks need trimming. Not that, then it could be a carbon ring. I had one last fall that I verified with the Lyman borescope and removed with JB Bore Paste.
It didn't take much work at all to remove the ring with the JB's. The price of the Lyman has made a borescope an affordable tool.

If you have a carbon ring, carbon cleaner soaks have never helped me, as far as removing it. JB will be necessary.

Barrelnut is correct. You need a borescope to verify what it is, where it is and your progress in removing it.

I have no evidence that they cause harm but abrasive paste makes me nervous. I use H1000 and get carbon rings too. I find it's best to clean for them every time I clean the barrel rather than letting them build up. My procedure:
Run a caliber size brush wet with bore tech carbon cleaner into the throat and spin it a couple of times. Put the bore guide in the chamber and let the cleaner sit a while. Take out the bore guide and scrub the throat/neck with a brush 1-2 calibers larger. Then do your normal cleaning. Bore scope it after the regular cleaning. I have a short cleaning rod (about 12" ) with a fixed handle from J Dewey. It's great for cleaning the throat area because I can twist the brush clockwise to clean.
Agree with others opinion about a scope. I have a really expensive one and recently tried a friends Lyman. I wish I'd saved the money and gotten the Lyman.

Use J-B Bore Cleaning Compound on the end of a slightly over sized bronze bore brush for your chamber. Spin it about 30 to 40 times at the end of the chamber. Do that each time you fire 60 to 80 rounds down your barrel. Do it religiously, and you won't see any carbon build up at the end of the chamber.

Well boys, I guess I got it out. In scrubbed the hell out of it with kg1 and also let it soak. However, I don't believe this was my biggest problem, I think it was the brass. I annealed the brass, longer than I normally do, and the saum is bugholing again. I just started to anneal as the Norma brass really needs it. I used templaq 750 and an annealease. I set the swell time to drop the brass just as the templaq "goes away". Obviously this was not long enough. I basically annealed the brass twice as long this time. I just trial and errored it my using a stopwatch. A total of 12 seconds per case was the magic number. I actually added .2 grains of powder to load to get it to come back and I have no pressure signs. I'm using 62.2 gr of H1000 moving the 180 gr hybrid 2900 fps. Could go higher but load bugholes and is easy on brass. I have 3 pieces of the Norma with 13 loading on them and still perfect. I am going to start cleaning for the carbon ring every time now though.

**** autocorrect is making me look like a hillbilly!! Ha! Y'all will get the drift!

My theory with the above is that the cold work hardened brass was not "soaking up" pressure. I know the necks were not too long as I use a chamber gauge to measure chamber and keep necks .008 below chamber length. You think my theory has any merit?

Wow 12 seconds is a really long time to anneal! I have the annealeez too

odoylerules said:

Wow 12 seconds is a really long time to anneal! I have the annealeez too

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Yeah, I have a feeling all brass is a little different...manufacturer to manufacturer and lot to lot....I have fired 30 rounds so far today (it's 98F here) and all is well. If I do my part, one ragged hole ever time!

morning, barrelnut is right. trim ur brass!! GBOT TUM

just country said:

morning, barrelnut is right. trim ur brass!! GBOT TUM

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Brass is trimmed every firing to .008" under measured chamber length using chamber gauge.

Barrelnut said:

Might be the case necks need trimming. Not that, then it could be a carbon ring. I had one last fall that I verified with the Lyman borescope and removed with JB Bore Paste.
It didn't take much work at all to remove the ring with the JB's. The price of the Lyman has made a borescope an affordable tool.

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I've used the JB's and also had good results with IOSSO bore cream on the carbon ring.