• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Carbon Ring ?

Pa.Mike

Silver $$ Contributor
I have been shooting for 52 years and have never heard or been aware of the "Carbon Ring" until I saw it mentioned on this forum. I mainly use Krieger or Brux barrels along with Dewey coated rods and always with a bore guide. I normally clean my barrels every 20 rounds during normal shooting sessions. Can someone please school me on the following:

1. Can the ring be detected without a Bore Scope?
2. Where in the bore is it usually located?
3. Can it be felt when the cleaning rod / patch is inserted in the bore?
4. What effect does it have on pressure?
5. What signs would make me suspect I may have a Carbon Ring issue?
6. Finally , what is the best method to remove and then prevent a ring from forming?

Thank you for any knowledge you can pass on!
 
1. Can the ring be detected without a Bore Scope?
NO

2. Where in the bore is it usually located?
In the chamber where the case neck ends.

3. Can it be felt when the cleaning rod / patch is inserted in the bore?
No.

4. What effect does it have on pressure?
Can and will affect pressure depending on the severity.

5. What signs would make me suspect I may have a Carbon Ring issue?
May or may not have signs.

6. Finally , what is the best method to remove and then prevent a ring from forming?
Bronze brush, CLR, abrasive cleaner. Typically you need an oversize bronze brush and you must rotate the brush in the neck area of the chamber. Need a bore scope to see what you are doing or not doing.
 
It’s fairly easy to remove if you clean it frequently and don’t let it build up and become hard.

Here’s a before/after pic

KAOhhkF.jpg


I use a 45 cal Ramrodz (basically a big Qtip) to keep it under control

HN2Lytg.jpg
 
what do you put on the qtip, jb or iosso?

Well, if I get at it after each shooting session it only takes (fill in your favorite solvent here) and a little bit of working back and forth. If it builds up and gets hard then a chamber brush or (fill in your favorite bore paste here) on the Ramrodz with a lot more back and forth.

On the pics above I used Boretech carbon remover
 
@Pa.Mike .... my input to your 6 questions:

1. Can the ring be detected without a Bore Scope?
Yes, but only when it has become a substantial build up

2. Where in the bore is it usually located?
At the chamber-end and on the convergent angle between the chamber and the throat.
See illustration below:

CarbonRing2.png

3. Can it be felt when the cleaning rod / patch is inserted in the bore?
Yes, but again, only when it has become a substantial build up

4. What effect does it have on pressure?
When the build up becomes enough to constrict on the bullet or case neck, pressure will rise. As it gets worse, so will the intensity in pressure.

5. What signs would make me suspect I may have a Carbon Ring issue?
- When pressure signs start to show up with commonly used ammo/handloads that normally would not yield pressure.
- If bolt closer becomes tighter/harder, can also be a telltale sign.

6. Finally, what is the best method to remove and then prevent a ring from forming?
Mechanical in nature cleaning procedures to clean it out, with follow up rituals going forward to all future cleanings. And highly recommend the purchase and use of a bore-scope to monitor the removal and for all future cleanings. With out the use of a bore-scope, don't know how anyone could conclude if they have the area truly clean and carbon free.

Edit:
Below is a Teslong picture of the "carbon ring area" in a uncleaned barrel with a case in the chamber as well.
Fallowed by 2 more Teslong pictures, how the "carbon ring area" of the barrel is being cleaned.

(Even though not much of a carbon ring present in the picture, it shows the starting buildup of carbon to the area)
Snap1.jpg

Snap2.jpg

Snap3.jpg

--------------------------------------------------------------------------------------------------------------
 
Last edited:
@Pa.Mike .... my input to your 6 questions:

1. Can the ring be detected without a Bore Scope?
Yes, but only when it has become a substantial build up

2. Where in the bore is it usually located?
At the chamber-end and on the convergent angle between the chamber and the throat.
See illustration below:

View attachment 1154498

3. Can it be felt when the cleaning rod / patch is inserted in the bore?
Yes, but again, only when it has become a substantial build up

4. What effect does it have on pressure?
When the build up becomes enough to constrict on the bullet or case neck, pressure will rise. As it gets worse, so will the intensity in pressure.

5. What signs would make me suspect I may have a Carbon Ring issue?
- When pressure signs start to show up with commonly used ammo/handloads that normally would not yield pressure.
- If bolt closer becomes tighter/harder, can also be a telltale sign.

6. Finally, what is the best method to remove and then prevent a ring from forming?
Mechanical in nature cleaning procedures to clean it out, with follow up rituals going forward to all future cleanings.
And highly recommend the purchase and use of a bore-scope to monitor the removal and all future cleanings. With out the use of a bore-scope, don't know how anyone could conclude if they have the area truly clean and carbon free.

Edit:
Below is a Teslong picture of the "carbon ring area" in a uncleaned barrel with a case in the chamber as well. Fallowed by 2 more Teslong pictures, how the "carbon ring area" of the barrel is being cleaned.

(There is not much of a carbon ring present in the picture, but it shows the starting buildup of carbon to the area)
View attachment 1154542

View attachment 1154543

View attachment 1154545

--------------------------------------------------------------------------------------------------------------
Donovan , This is one of the best post on this site . A+ the boss needs to pin this one .
 
The stuff at the front of the neck part of the chamber, up in the corner, not on the leading edge of the freebore is just powder fouling. Hard carbon forms where Dusty's picture shows it, going forward from the edge of the freebore. and to my knowledge will not be removed by any liquid solvent. It is hard enough that it will not mark a clean white patch.
 
I nominate this thread for sticky status. Especially with the borescope pix and dmoran's excellent graphics, I think this thread answers a lot of questions.
 
@Pa.Mike .... my input to your 6 questions:

1. Can the ring be detected without a Bore Scope?
Yes, but only when it has become a substantial build up

2. Where in the bore is it usually located?
At the chamber-end and on the convergent angle between the chamber and the throat.
See illustration below:

View attachment 1154498

3. Can it be felt when the cleaning rod / patch is inserted in the bore?
Yes, but again, only when it has become a substantial build up

4. What effect does it have on pressure?
When the build up becomes enough to constrict on the bullet or case neck, pressure will rise. As it gets worse, so will the intensity in pressure.

5. What signs would make me suspect I may have a Carbon Ring issue?
- When pressure signs start to show up with commonly used ammo/handloads that normally would not yield pressure.
- If bolt closer becomes tighter/harder, can also be a telltale sign.

6. Finally, what is the best method to remove and then prevent a ring from forming?
Mechanical in nature cleaning procedures to clean it out, with follow up rituals going forward to all future cleanings. And highly recommend the purchase and use of a bore-scope to monitor the removal and for all future cleanings. With out the use of a bore-scope, don't know how anyone could conclude if they have the area truly clean and carbon free.

Edit:
Below is a Teslong picture of the "carbon ring area" in a uncleaned barrel with a case in the chamber as well.
Fallowed by 2 more Teslong pictures, how the "carbon ring area" of the barrel is being cleaned.

(Even though not much of a carbon ring present in the picture, it shows the starting buildup of carbon to the area)
View attachment 1154542

View attachment 1154543

View attachment 1154545

--------------------------------------------------------------------------------------------------------------
Is the black line the carbon ring (seems as though it is not a carbon ring from the discussion above. What is it and why is it carbon color?)? And how bad is it? My chamber has this exact ring as yours.

This is what I have (I put a piece of brass in for reference.
I also drew a red line to surround the black line I'm referring to in a second image
 

Attachments

  • Screenshot_20210716-144551_Gallery.jpg
    Screenshot_20210716-144551_Gallery.jpg
    160 KB · Views: 106
  • Screenshot_20210716-144551_Gallery.jpg
    Screenshot_20210716-144551_Gallery.jpg
    164.8 KB · Views: 103
Last edited:
Is the black line the carbon ring (seems as though it is not a carbon ring from the discussion above. What is it and why is it carbon color?)? And how bad is it? My chamber has this exact ring as yours.

This is what I have (I put a piece of brass in for reference.
I also drew a red line to surround the black line I'm referring to in a second image

The black line you have referenced is a carbon ring at the end of the chamber. It is not bad at all.

I am puzzled by what I see though. There shouldn't be a nice clean area between the case mouth and the carbon ring. This doesn't make sense. It looks as though the mouth of the case is 10-20 thousandths behind where you have been shooting it. Does that make sense?
Screenshot_20210716-144551_Gallery.jpg

The "alligator/firecracked" area is the transition between the chamber and the throat. Forward of this, is the area that hard carbon can build up in, referenced by Boyd in his post. In severe cases, the area can build up to the point it causes increased pressure. This hard baked on carbon is the subject of another current thread. I have only been able to remove the carbon in the throat with Iosso.

The carbon ring you have, I have usually been able to remove with a bronze brush one caliber larger than the barrel, turned carefully at just the right place in the chamber. (trial and error/success)

The carbon ring you have will not cause pressure at this time. If left to build up it can, but usually takes many rounds. (see Donovan Moran's two arrows)

This is my opinion looking at the pics you have provided and comparing it too what my barrels look like in my bore scopes. I can't be 100% certain, so again, it is my opinion.

Jim

Edited: Never mind, I think Straightshooter explained the line. A shadow makes sense. Insert the borescope from the other end and look.
 
Last edited:
Is the black line the carbon ring (seems as though it is not a carbon ring from the discussion above. What is it and why is it carbon color?)? And how bad is it? My chamber has this exact ring as yours.

This is what I have (I put a piece of brass in for reference.
I also drew a red line to surround the black line I'm referring to in a second image

No, it doesn't appear to me to be a carbon ring as commonly referred to. When I got my first bore scope I was puzzled when saw this area too. It wasn't until In inserted my bore scope from the muzzle end that I saw this disappear, as it was more of a shadow of the Second Shoulder of the chamber that leads into the free bore area. I could easily enough get rid of the carbon rings shown before that second shoulder, but because this area looked like some carbon build up, I'd scrub and scrub to try and remove it with no success. So, try and insert your bore scope from the other direction and see what you see. I'd bet that most likely, you won't see any carbon, since the other area ahead of your case looks completely carbon free (no "carbon ring").

Here's a pick I took from a chamber of mine where you can see the carbon ring partially removed and the shodow of the second shoulder looking much like carbon coated:
Carbon Ring.jpg
 
Last edited:
There is usually some confusion in these discussions because of terminology issues.

Powder fouling that builds up at the end of the neck part of the chamber, in that little corner at the bottom of the 45 degree chamfer leading up to the beginning of the freebore can be removed with ordinary solvents and a twisted one size larger than bore bronze brush, or any number of other methods that do the same thing. A little powder fouling here is not an issue unless it piles up too much, and then it can be.

There is another type of fouling, that starts in a slightly different location, just past the TOP of the chamfer, right at the leading edge of the freebore. At that location the pressure and heat transforms ordinary powder fouling into something that no solvent can touch, and which will not show color on a patch. It requires something like IOSSO or JB Bore Clearner to remove. I find IOSSO more effective. If someone wants to know how I use it, PM me. This sort of deposit has been referred to as hard carbon. It starts where I have described and if not removed will continue progressively down the throat and beginning of the rifling.

Up until recently, I thought that the only think you could do to address hard carbon was to remove it periodically, scheduled by experience and round count, hopefully before it had gotten to the point of degrading accuracy. Now, I have a new method to try, based on the experience of a friend who shoots a lot of matches and owns a bore scope. It involves applying Kroil, waiting about four minutes, applying some Kroil to a bronze brush, and stroking it up and back, and then waiting another four minutes before starting ones regular cleaning method. Evidently this removes the powder fouling better than normal solvent cleaning, so that it does not build up. My friend shoots short range score and group, and cleans more frequently than some long range disciplines often do.

Up until recently, the only way to know what was going on inside of your barrel was by the use of a borescope, and they were too expensive for most shooters to justify owning. This has all changed with the advent of the Teslong bore scopes. They work very well and are very inexpensive. I suggest that anyone who is not familiar with them do some serious research. You still need a bore scope, but thankfully now anyone can afford one.
 
Edited: Never mind, I think Straightshooter explained the line. A shadow makes sense. Insert the borescope from the other end and look.

No, it doesn't appear to me to be a carbon ring as commonly referred to. When I got my first bore scope I was puzzled when saw this area too. It wasn't until In inserted my bore scope from the muzzle end that I saw this disappear, as it was more of a shadow of the Second Shoulder of the chamber that leads into the free bore area. I could easily enough get rid of the carbon rings shown before that second shoulder, but because this area looked like some carbon build up, I'd scrub and scrub to try and remove it with no success. So, try and insert your bore scope from the other direction and see what you see. I'd bet that most likely, you won't see any carbon, since the other area ahead of your case looks completely carbon free (no "carbon ring").

Here's a pick I took from a chamber of mine where you can see the carbon ring partially removed and the shodow of the second shoulder looking much like carbon coated:
View attachment 1267696
Wow, now that is an eye opener! Turns out I've been concerned about a shadow

Here is a shot using the borescope from the other end...the "carbon ring" I could not remove was just a shadow (I also found other areas in the bore that were also shadows by going the opposite direction):
 

Attachments

  • Screenshot_20210718-085703_Gallery.jpg
    Screenshot_20210718-085703_Gallery.jpg
    67.4 KB · Views: 60

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,572
Messages
2,199,130
Members
79,004
Latest member
4590 Shooter
Back
Top