6 Dasher carbon fouling problem

[AndyW]

I have a 6 Dasher that severely carbon fouls. After cleaning I start to get pressure spikes around the 15-20 round mark and it progressively gets worse. First 10-15 shots zero issues, then sticky bolt lift, then after a few rounds of sticky bolt brass will show extractor mark. I have backed the load off (one grain) and I get the same result.

Here are the details;

-Krieger barrel- .236 bore
-RL 15 powder- 32.9 grains
-BR4 primer
-Berger 105 seated .015 into the lands

Barrel was broken in, does not copper foul.

This is the first barrel that I have had this issue with. I was told that trying 450 primers may help. Anyone else run into this?

 

[johara1]

If it were me i would try an other powder and see if the same thing happens. Try varget may give you better results,but the big one are you getting the carbon out to start with? Do you use a bore scope? Where is the carbon build up?.......jim

 

[762willdo]

you have a carbon ring in the throat common for re-15 you will have to work hard to get it out.
VARGET VARGET VARGET VARGET!

 

[AndyW]

I do not have a bore scope. I am soaking with Butches and brushing, I am sure I can feel it when the carbon is gone. As well No pressure issue after I clean.

I will give Varget a try, thanks fore the input.

 

[fdshuster]

Andy: Butch's, as good as it is (my main cleaning solvent), will not touch the hard, baked on carbon fouling. I'm not criticizing RL powder, understand many are using it and are happy with the results, but I have found it to leave a lot of carbon, as verified with my borscope. I am using Varget exclusevely. Your problem does sound like the typical one of a build-up of carbon. If you were able to look inside the barrel you would see coal black, ugly streaks with the caked on carbon. Cleaning patches coming out white are a false indication of a bore being carbon free. You gotta go after it aggressively. I use JB and a bronze brush, but others have other products & methods. We had several lengthy discussions on this site about carbon removal recently, so you might want to review those postings.

 

[fdshuster]

Donovan: One of our local premier rifle builders, and winning BR match competitors also prefers Iosso, and when my can of JB is empty ( almost now), I'll break-out the tube of Iosso that I have. I don't feel bad about using either/ have heard too many good reports about both.

 

[johara1]

I never had a carbon fouling, with RL-15, maybe your load is too low. i shot 33+ gr with the 115's. I moved on to other powders since but Varget isn't one of them. Some have good luck with Varget,i didn't and there are many records held with RL-15 so i would say your loading or cleaning is the key to your problem. I did shoot as many as 75 shots without cleaning with out a problem and it was RL-15,dirty i don't think so.....jim

 

[queen_stick]

I just ran into a carbon fouling problem for a second time in the past few weeks... in a 6BR!!! That cartridge is not known for creating a carbon ring in the throat, but I did it, and I've done it twice now. The second time happened to me in a match last weekend, and it killed my group and score.

Primary reason that carbon is building = RL15... It's the dirtiest powder I've ever used, but my gun loves it, so I'll keep using it.

The reason that BOTH of us are getting carbon fouling = improper cleaning regimen.

I now know that my cleaning regimen was not getting all of the carbon out of the barrel. When I thought it was gone, the ring would build back up in less than 50 rounds... That means the carbon is not completely out! My barrel is currently soaking in Hoppe's BR. When I clean it tonight, the bronze brush is going to get a workout, followed up by a bunch of patches with JB slobbered all over em'!

With that said, I also believe I'm going to give up my nylon brushes and use bronze brushes from now on. When that carbon ring was in the throat I tried to knock it down with a nylon brush. I scrubbed for 5 minutes, and it was still there. I switched over to a bronze brush, and that thing was gone (to the point I could no longer feel the restriction in the throat) in about 10 passes. I believe I should have started using the bronze brush a long time ago... maybe that would have prevented the carbon build up.

 

[queen_stick]

Thanks Donovan,

I made it sound a little more extreme than what I'm planning on doing tonight

I'm going to be a little more aggressive with the JB than I'd like to be in my next cleaning session. The reason is I'm approaching 500 rounds on the barrel, and have not used Iosso, JB, or the like... it's over due (as I'm now learning the hard way). I need to make sure that junk is out of there. I have a few cleaners on hand, including Sweet's, so maybe I'll let that stuff soak in there for a bit before going too crazy with a brush.

I'm a "load and shoot" type of guy, so I don't like getting too caught up in things like this. But, I've obviously failed in ALL of my previous cleaning sessions, so my attention is now piqued!

I'm going to be testing some loads with Varget at 1K in 2 weeks. If I can find something that shoots as accurate as my current load with RL-15 (2.5" vertical), then I'll switch over in a heart beat!

Walt

 

[johara1]

Walt For a little more info. i almost never use a brush, i don't use jb's. I found warthog a lot better,Iosso works better for me,I don't soak it over night,if i brush i remove the brush and never pull it back through. I bore scope it after cleaning, Only carbon is right in front of the case not in the throat. and that is very easy to remove and not with a brush......jim

 

[johara1]

Donovan, I found that if i use a bronze brush and a brass jag,i spray with non chlorinated brake cleaner after use and they will last a long time.I have not had to replace them this year. Hope to see you at the National..........jim

 

[deadlyswift]

Andy: Butch's, as good as it is (my main cleaning solvent), will not touch the hard, baked on carbon fouling.

I can't stress this point too much! Don't get me wrong just as (fdshuster) I use Butches a lot! How ever Butches will not touch carbon!! I have tried many liquid solvents, and the best one to get carbon out is Mpro 7, but it still will not get it all out. JB bore paste does the job for me. It is good stuff and I see no evidence of it harming my barrels. As (fdshuster) I confirm things with a bore scope. I will add that Montana Xtreme bore solvent is also a really good solvent. Recently tried it and I'm currently finding myself using it more than Butches now days.
Thanks
Mark

 

[762willdo]

GM top engine cleaner works for me, it KILLS carbon!

 

[lynn]

Donovan
Have you ever used a short case to blow the carbon out?
Next time you ruin a piece of brass shorten the neck length up considerably and load it back up.
Borescope the carbon before firing and after firing with the real short necked case.
Lynn

 

[johara1]

Lynn, If your talking about the carbon build up at the end of the chamber? If you are, the best way to remove it is a long case expand it to the neck diameter and sharpen it with conferring tool. Put it in and close the bolt, it cuts the carbon right out. Just wipe it away...........jim

 

[AndyW]

Guys;

Thanks for the input. Got the carbon ring out with some JB's and verified it with a borescope. I will try varget and see how that goes.

 

[flatlander]

As the guys with Hawkeyes have confirmed, you'll never be able to tell if the carbon's completely removed without a borescope. And the longer you leave the carbon in (and continue to shoot over it) the harder it is to get rid of. From what I've seen, IOSSO paste gets the carbon out faster than J-B, and that's all I use nylon brushes for.

 

[BulletBob3701]

In the January 2006 issue of Precision shooting is an article on bore cleaning "An Arduous Journey Through the Lilliputian World Of Lands and Groves" by IRV Benzion. After testing lots of solvents He recomends using Slip 2000 Carbon Cutter to break down carbon and then Bore Tech Eliminator for copper. If you go to Slip 2000s web sight there is a reprint of the article. He adds that to get all the carbon out sometimes a little scrubbing with JB is needed.

I've used this with great success and also Wipeout and Carb out when I'm out shooting prairie dogs.

Bob

 

[fdshuster]

Bob: Slip 2000 was one of the "miracle" carbon removal products I tried, when it first came on the market several years ago. As verified with my borescope, it did remove some of the carbon from the tops of the lands, and center section of the grooves, but it would not touch the carbon that was built up in the corners, where the lands meet the grooves. I was really impressed with it when I first tried it to remove the carbon from fired case necks. It took it all off with little effort. But was then disappointed when I saw how ineffective it was in the bore. The difference? The carbon on the case necks was not subjected to the intense heat that the bore was. Carbon in the bore, beginning about 3" to 4" in front of the chamber & extending for about 6" to 7" was baked on from the intense heat, some say at well over 2000 degrees F.

 

[7.62X51]

Try Bore Tech C4 Carbon Remover but give it some time to work.
Example...I had a 308 Win. barrel that had thick crusty, baked on carbon on the crown from
using a muzzle brake so I set the rifle upright and lay a patch wet with on the crown.
Every 15 mins. or so I gently rubbed the crown with the patch and the carbon started
lifting off. I did this over a 2 hour period or so until the crown looked, well, like the day
it was crowned ( Lilja s/steel 3-groove 1:12 .308 barrel ) Wet a patch with C4, push it
into the throat and leave for a couple hours to soak then brush. I think you will the pleasantly
surprised. Just be patient and let the chemicals do their work.

cheers, Chris