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Carbon ring !

Texas Solo

B.S. High Master
I have 325 rds. On my 6 dasher. It shoots incredibly well. I decided to bore scope to ensure my cleaning routine is working. The bore looks very clean. But...I see a carbon ring starting to form. I'm confused how it's happening.
Brass chambers very well, has never been trimmed. Alpha. Berger 105 Hybrids & Varget. Seated to, but not in, the lands.
I guess I'll have to scrub it out before it gets worse. But I'd like to know why it's happening.
Any thoughts welcome.
 

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It’s just a normal part of shooting. The more you clean and stay on top of it the easier it is to deal with. It hardens with time so cleaning asap while the gun is still warm seems to help. Or run a couple wet patches through before you leave the range to keep it soft.
 
Well I don't clean "ASAP", but I do clean same day when I get home. After the bore, I clean the chamber & throat as an additional step. I use a brush wrapped with a patch & WipeOut for the chamber & throat. I just fear doing damage with brushes.
 
Well I don't clean "ASAP", but I do clean same day when I get home. After the bore, I clean the chamber & throat as an additional step. I use a brush wrapped with a patch & WipeOut for the chamber & throat. I just fear doing damage with brushes.
That’s asap enough. For carbon brushes are your friend! Just don’t pull them backwards while they’re still in the bore and there’s nothing to worry about.
 
You will not damage a barrel with a brush.

Forum Boss: I generally concur, if the person is using a proper bore guide and is not overly aggressive. However, I have inspected multiple barrels showing damage to the edge of the crown caused by sawing back and forth with bronze brushes. I know that many successful short-range shooters brush very aggressively, but some of those guys also regularly re-crown their barrels or toss them after 800 rounds.

Unless there is an extreme time constraint I recommend using a bronze brush in one direction, then removing it after it exits the barrel, and cleaning it with solvent, then putting it back on the rod and entering from the chamber end. That said, there are some barrels and types of fouling where back and forth movement in the throat area might be required. But I think most people, with custom barrels, will benefit by being conservative, if they clean before the carbon hardens.
 
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Well I don't clean "ASAP", but I do clean same day when I get home. After the bore, I clean the chamber & throat as an additional step. I use a brush wrapped with a patch & WipeOut for the chamber & throat. I just fear doing damage with brushes.
An over-sized Iosso bore brush coated with C-4 on a short cleaning rod spinning in that area will do wonders. Try 20 revolutions and check it. May take more. If the C-4 fails Iosso on the brush is the next step.
 
It does help to soften up that carbon ring before trying to scrub it out. I've tried Wipe-Out with accelerator, CLR and a solution of Lemi Sine (a concentration that acts like CLR). The Lemi Shine concentration works reall well for me leaving a soaked bore mop on the carbon ring for 15-20 minutes. Then, a little scrubbing there with a brush and a little IOSSO bore cleaner.
 
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That carbon buildup appears to be at the end of the neck between where the case ends and the throat begins. Get a bronze brush a little oversize for the neck diameter and put it on a short chamber brush (one without a rotating handle...like the Sinclair). Drip a little carbon cleaner on it and short stroke/rotate it until the ring is gone. You will NOT hurt the steel. If I get a little ring forming in the beginning of the throat, I do the same. I can't count the barrels I've cleaned with this method and have seen no harm. For the record, I also bronze brush the entire bore every cleaning using BoreTech carbon cleaner and the targets don't know the difference. Oh, the HUMANITY!!! Get after it and don't sweat it.

edit- any carbon cleaner would be fine, just use nothing that contains copper removing chemicals as it will destroy bronze brushes quickly.
 
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I am not being flippant but educate me on 'carbon ring'. I never heard of one before I joined this forum so I would like to learn more about this issue.

From what I understand, the carbon ring forms at the junction at the end of the case neck to the beginning of the throat. Is that correct? At least that is where a dark ring appears in my rifles.

If that is so, how does that degrade accuracy since it occurs behind where the bullet jumps and engages the rifling?

I have several thousand rounds through a variety of rifles which seem to be holding their varmint grade precision with routine cleaning of a simple solvent such as Hoppe's 9 or Shooter's Choice and a bronze brush. The most rounds I ever put through a single rifle was a little over 5000 through a 222 Remington which held its precision with routine cleaning. Eventually the groups did start to open.

I have carbon rings in all my rifles (verified with a smith's or a friend's bore scope), yet they seem to continue to shoot very well without any chambering issues at all. Granted I am not shooting to benchrest standards but varmint level standards of 1/2 to 5/8 moa.
 
Carbon rings show no effect on anything until they grow to the size that they touch the bullet or pinch it. That is generally when you begin see pressure in an otherwise safe load and you accuracy degrades . This is what happened to me in my 6BR Norma.
 
I am not being flippant but educate me on 'carbon ring'. I never heard of one before I joined this forum so I would like to learn more about this issue.

From what I understand, the carbon ring forms at the junction at the end of the case neck to the beginning of the throat. Is that correct? At least that is where a dark ring appears in my rifles.

If that is so, how does that degrade accuracy since it occurs behind where the bullet jumps and engages the rifling?

I have several thousand rounds through a variety of rifles which seem to be holding their varmint grade precision with routine cleaning of a simple solvent such as Hoppe's 9 or Shooter's Choice and a bronze brush. The most rounds I ever put through a single rifle was a little over 5000 through a 222 Remington which held its precision with routine cleaning. Eventually the groups did start to open.

I have carbon rings in all my rifles (verified with a smith's or a friend's bore scope), yet they seem to continue to shoot very well without any chambering issues at all. Granted I am not shooting to benchrest standards but varmint level standards of 1/2 to 5/8 moa.
The common theory is IF the brass grows longer than the chamber neck area the carbon ring will cause pressure as the neck will be pinned in that area between the carbon ring and case mouth.
 
In a rimfire caliber it's common to see the carbon ring cause accuracy to drop off in what was an excellent brand/round/lot #. It can cause a bit of a tight chambering issue as well, especially in a match chamber. I don't know of any plus to having a carbon ring no matter the cartridge.
 
Some of this depends on how much a particular powder fouls, the relation between trim and chamber length, and the amount of bronze brushing that is done in a normal cleaning. If you are shooting a clean powder, brush quite a lot when you clean, and keep your brass trimmed so that it does not extend over the ring, then you may see no effect, and probably should not stay up nights worrying about how to remove it, as long as it stays about the same size over time. I know that this may seem like heresy but so be it.
 
It’s just a normal part of shooting. The more you clean and stay on top of it the easier it is to deal with. It hardens with time so cleaning asap while the gun is still warm seems to help. Or run a couple wet patches through before you leave the range to keep it soft.
This is sage advice. After barrel cools to ambient temp that carbon begins to harden over time and requires much more effort to remove. I have been able to decrease usage of abrasives by bringing my cleaning supplies with me to range or match and clean before going home. It does make a difference.
 
This is sage advice. After barrel cools to ambient temp that carbon begins to harden over time and requires much more effort to remove. I have been able to decrease usage of abrasives by bringing my cleaning supplies with me to range or match and clean before going home. It does make a difference.
Being a BR shooter I never leave home without the cleaning stuff, a brass brush will not hurt your barrel, kind of sick of hearing that. I'd rather lose 300 total rounds on a barrel that shoot a dirty barrel that won't shoot a 1/4" MOA or less (a lot less for precision shooting). Clean and clean well your targets will love you for it! (and you'll love your targets!).
 
Well I don't clean "ASAP", but I do clean same day when I get home. After the bore, I clean the chamber & throat as an additional step. I use a brush wrapped with a patch & WipeOut for the chamber & throat. I just fear doing damage with brushes.
To not frequently scrub bore with good quality loop end bronze brushes could indirectly cause a bore condition that could be potentially damaging to remedy said bore condition. What I mean is if a person is scared of bronze brushing and forgoes brushing thoroughly then hard carbon build-up will eventually occur from the throat and the first 6” or so up the barrel. Frequently & carefully bronze brushing (while barrel is still warm ideally) will help minimize that hard diamond like carbon build-up. Even if a shooter stays on top of it and brushes regularly, in most barrels that hardened carbon from heat and pressure will still build up and at some point an abrasive (I like Iosso and Thorroclean) will likely need to be used to remove such carbon or inaccuracy and pressure spikes will ensue. If a person refuses to use a bronze brush this condition will get out of hand and result extremely hard and tenacious carbon buildup and the only way to remove it could potentially damage the bore…Hollands Witches Brew directly on a bronze brush can remove such a neglected bore but I’ve found that even as aggressive as Withces Brew is (very hard Aluminum Oxide suspended in Kroil or Kroil-like substance) it can take many cycles of brushing the abrasive and then checking with borescope to see progress. I don’t like to use such a method because damage can happen even when using utmost care with such a hard abrasive directly on bronze brush. So not using a bronze brush is a lot scarrier of a proposition to me than worry about damaging my barrel with soft bronze brush using the following solvents depending on my mood that day…Butches, Montana Extreme, Hoppe’s/Kroil mix, Shooter’s Choice/Kroil mix, Bore Tech C4, Free All penetrating oil, KG1,
or Sharp Shoot R/Wipeout Tactical Advantage.

The soft bronze will not harm the barrel but carbon, copper, and primer residue contain abrasive's that are picked up by the brush if patches and solvents are not used prior to bronze brushing. So it is best to remove as much of said abrasive fouling using solvent and patches only until patches show no black. Then thoroughly and carefully use a bronze brush and solvenT. I’m not even gonna mention whether to brush both ways (I brush both ways as I feel it more effectively removes fouling brushing both ways). Some brush like I do and others remove brush after it exits bore.

Brush will not harm barrel if common sense is used along with use of proper 2 piece bore guide with bushings while employing good technique with no bow in rod during brushing. There is not really an equally effective alternative to bronze brushing to keep ahead of carbon build up. My brushes are made by Pro-Shot and Dewey with no preference between the two. I brush every cleaning which is immediately after I finish shooting the respective rifle for the day. Although brushing every cleaning while barrel is still warm does minimize build-up of hard carbon, I still use Iosso following their instructions with the Iosso stuff blue Nylon brushes every 150 or so rounds sad I have found that to be a good cadence. When I use abrasives I short scrub from throat to about 6-8” forward of throat and that’s as far as I go with abrasives as the hard carbon doesn’t really build up much past that point. My first shot after using abrasives may be a little slower but after that my shots are all back into group. My barrels lasyy to s long time using this method. I also feel that use of Iosso every so often as the barrel ages as far as round counts is beneficial for another reason and this is it smoothes down the fire cracking/heat-checking in those first few inches of the barrel which may help prevent or minimize said cracking causing copper fouling due to rough bore condition.

I’m a big believer of bronze brushing as well as judicious use of proper abrasives to mechanically remove hard carbon which liquid solvents fail to remove. Accurate barrel life will most likely be reduced if one allows the hard carbon build up to go unchecked. But everyone has their own preferences, superstitions, and methods of dealing with the bore conditions in their own barrels.
 
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Some of this depends on how much a particular powder fouls, the relation between trim and chamber length, and the amount of bronze brushing that is done in a normal cleaning. If you are shooting a clean powder, brush quite a lot when you clean, and keep your brass trimmed so that it does not extend over the ring, then you may see no effect, and probably should not stay up nights worrying about how to remove it, as long as it stays about the same size over time. I know that this may seem like heresy but so be it.
So, if cleaning with a properly fitting bore guide while cleaning the barrel, how does the carbon ring get touched? I assume this must be a separate step in the cleaning process without a bore guide.?
Relatively new to this compared to some, and this has always puzzled me.
 

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