The carbon ring...

[lurcher]

I have been reading a few posts on here about pressure effects caused by formation of a carbon ring ahead of the throat.

I was wondering what is the best way to check for and remove the ring. I read that some people short stroke with a brush and abrasive. Is an abrasive really required?

Just interested tp hear peoples thoughts on the ring and how they monitor it and remove it and how often they remove it. I understand it is more of an issue in smaller calibers?

 

[Keith Glasscock]

I've had it in my F/TR rifle. After that, I used a patch of JB bore paste every 3-400 rounds just to make sure. I give it a short ~6" stroke for 15 passes. I haven't had any problems yet. Note that you are trying to remove something right at the beginning of the rifling.

I recently bought a borescope. Much easier. I just look for it and take care if it when needed.

 

[Nomad47]

Not positive here, but I believe that when a "carbon ring" is mentioned that it is just ahead of the case neck (at the end of the chamber) and before the throat.

For a 6mm cartridge, I use a 7mm brush to remove it. Think of the diameter of the neck of a loaded round.

 

[lpreddick]

like Nomad47 says. if you can get a copy of tony boyer's book he has a diagram of the chamber and the location of the "carbon ring". the length of the ring is the difference between your chamber length and case length...a sinclair chamber plug will give you the first measurement. abrasives and short stroking probably doesn't get this really baked on carbon deposit out. a bronze or stiff nylon brush dipped in jb ROTATED in the end of the chamber will eventually get it out. once established, a WHOLE LOT OF ROTATING is needed. borescoping is extremely helpful. how important is removal of this "ring"? i believe VERY IMPORTANT! an established and thick ring can probaly crimp the neck of a case that is slightly longer than the previously fired ones.

 

[CaptainMal]

Very sore topic for me as I have been a victim of it. Darn carbon deposits can and do go past the extended neck and into the first part of the rifling also. Borescope will show the sad news. Case heads will swell, primer pockets will expand and you will flat out lose the barrel.

I know. I know.

Iosso bore paste, Bore Tech C-4 and other carbon-specific solutions regularly applied and scraped into the problem areas will correct the problem if it's not too bad or was allowed to build too much. Regular use will keep the problem in check. Using Varget exacerbates the problem

 

[artbosco]

Spin an over sized brush with JB paste on its tip, about 30 revolutions, at the end of the neck chamber, after about every 50 rounds.

Clean it out thoroughly with solvent when done.

Clean the entire barrel as you normally would.