Carbon ring.

AWS

AWS

Custom Accessory Maker & Retired PM Staff
I bought a nice barrel and started out ok and cleans up well. I started having problems when I tried a new bullet. I usually seat bullets old-school, touch the lands and seat deeper untill it doesn't touch. I noticed that instead of seeing land marks I had smudge ring all around the bullet. It really looks like the throat is too tight.

Well it was frustrating enough to cause me to buy a bore scope. Turns out I have a thick hard carbon ring between the case mouth and the lands. I tried everything to get it out, carbon remover, special pads soaked in carbon remover and placed over the ring, lots of hard scrubbing with brushes and carbon solvent, it helped but the ring was never really gone and built right back up.

I've never experienced this in 60yrs or shooting. I'm on the verge of ordering another barrel. So the barrel is either salvageable or toast. Today I chucked up an oversized bronze brush and had at it with my trusty drill, talk about major chunks of carbon coming out and so far no damage to the lands.

Tomorrow it goes back to the range to see how it goes.

Anyone else ever run into something like this
 
I've only had carbon ring issues in one rifle. That particular rifle is an "Improved" version and the brass ended up getting trimmed a little on the short side. In my opinion overbore cartridges and brass that is on the short side compared to the chamber tends to cause premature carbon rings more then anything else.

You probably don't have a print of the reamer used to cut your chamber and you won't be able to measure it, at least not very accurately, until your chamber is 100% clean of any fouling but if you ever do get it spot less clean they make these little chamber length gauges that'll allow you to measure your chamber and you can compare the measurement to the overall length of your brass to see if it's on the short side. A lot of people trim the necks based off of whatever SAAMI spec says they should be but not every chamber is actually the same which often results in over trimmed brass.
 
I've been cleaning with an over size brush and drill in the neck for a long time and it doesn't hurt a thing. B23 makes good points, and I'd add that some powders are worse than others, I've noticed more rings with 8208 than anything but I still love that powder.
 
This is a 20P, I did chamber an sized piece of brass and ran the bore scope in. There is some space between the end of the case and the end of the chamber and that is where the carbon ring was. This was a newly made piece of brass untrimmed but is very close to my trimmed brass. I might let my brass grow some and set the trimmer longer. It is also a Savage nutted custom barrel so I might turn it in a bit if I can and push the shoulder back a smidge.
 
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I've read a lot about GM top engine cleaner and from what I understand the original formula was great but have toned it down recently

I just recharged the bore scope that and the chamber is clean and no more smudge rings on the bullets. See how long it lasts, at least it's easy to check now.

The bore scope has been a great investment, saved me having to buy a new barrel. I've been surprised by a couple used barrels by how bad they look and how well they shoot.

I bought the teslong with the handheld screen so I can use it anywhere..
 
I’ve heard lapping is the best way to get rid of hard carbon. U could try scrubbing with jb bore paste, won’t hurt anything
 
I have the teslong and it plugs right into my phone. Only charge needed is your phone. You can also take pics and video I believe.
 
AWS said:
I've read a lot about GM top engine cleaner and from what I understand the original formula was great but have toned it down recently

I just recharged the bore scope that and the chamber is clean and no more smudge rings on the bullets. See how long it lasts, at least it's easy to check now.

The bore scope has been a great investment, saved me having to buy a new barrel. I've been surprised by a couple used barrels by how bad they look and how well they shoot.

I bought the teslong with the handheld screen so I can use it anywhere..
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yes correct.. this is the old original hard to find 'Banned' carcinogenic GM top engine .... LOL
This stuff melts hard carbon like butter. I scored 2 cans of it more than 20+ years back, and that more than a lifetime supply for me . And I DO Wear Gloves when handling it.
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Brownells sells felt cleaning pellets that come with a special jag that screws into the pellet. I take a patch of CLR and drape it over the end of the jag and insert it into the neck of the chamber. 15 minutes later I remove the patch and add a little Iosso paste to the felt pellet and give it about a dozen turns in the neck and the carbon ring is completely gone. It's safe and effective.
 
BangPop said:
Brownells sells felt cleaning pellets that come with a special jag that screws into the pellet.
Click to expand...
They also have same pellets w/an abrasive embedded in them. Have used those on heavy copper fouling.
Have not experienced the dreaded carbon ring, even when using moly coated bullets. In fact, since finding Tactical Advantage, use only stiff nylon brush to remove normal copper and carbon fouling in bore.
If I ever do encounter the ring, I'll try soaking overnight w/wet patch of TA, followed by impregnated felt pellet and see if that works. Suspect it would take multiple applications, but who knows?
 
KG1 Carbon remover is the best I have found personally. It was the only thing that I could count on to easily remove the carbon deposits on the magazine tubes and gas ports of my Remington 1100 and 1187 shotguns when I was heavy into sporting clays. I ran Red Dot powder which ran a little on the dirty side and would really build up on the mag tube. KG1 would literally melt the carbon away. I tried a bunch of other solvents, but they required a lot of elbow grease.
 
I set up a Wilson case trimmer to trim to 1.760 instead of 1.750, maybe making the gap in front of the case mouth smaller will minimize the carbon build up. I can always let the necks grow more if needed.

A little curious as to how you would make a steel cased 223 longer to reach the carbon ring in front of the case mouth? Or size it down to .204, I've never tried to size steel cases.
 
As far as sizing down to 204, why not use a brass case. Sizing it down should lengthen neck enough to catch the ring and brass, while it probably wouldn't last as long as a steel case should still scrape softened carbon, I would think??
 


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