Bartlein RV contour on a TL3. Friend of mine did it who's sort of just getting started. It shoots though. Maybe it's a chambering issue.
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Doubt it's a chambering issue. Mine was done by a regarded smith, don't want to say his name and have it associated with any issues. Mine does it bad with H4350 and I'm thinking it has to do with not getting a complete burn and the suppressor keeping shit in the barrel from the added back pressure.
Was my theory as well at least on the back pressure part. Despite RL16 supposedly having a 96% burn rate according to QL in an 18" barrel, might need something faster. I'll work up a load with varget tonight as QL says 99% burn rate for it.
Shots 9 & 10 on the right and a previous shot out of the first eight on the left.
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With regards to the carbon ring... I had a similar nasty carbon ring on a 6mmAR. I mention that because it was particularly hard to diagnose in a gas-gun because there was no 'feel' on bolt close (or opening) to help catch it. Brass looked like crap anyway because it was over-gassed so ejector marks were easily missed until it was seriously over-pressured and intermittently failing to eject and a few primer pockets were loose on subsequent reloadings. I'd back off my powder charge and get a bit of accuracy and reliability back for awhile, then it would fall apart again. I was ready to trash-bin the barrel despite a relatively low round count. I finally diagnosed it the same way you did, measured a shorter length-to-lands and knew the throat didn't wear that direction...
I cleaned and soaked it pretty thoroughly with C4 & then short stroked the throat with JB bore paste, re-measured length-to-lands and it was back out where I expected it to be. I brought the powder charge back up to the original load (30.3 gr Varget) and accuracy was back!!!... for about 30 rounds... and the carbon ring was already creeping back! Best guess is that I had let it go for so long and get so hard & established that the JB and C4 had only knocked it down a little bit, but not removed it.
Anyway, the point I was getting at is that out of frustration (and because the barrel was pretty much a tomato stake with that carbon ring) I took its removal to the next level. I took a cheap brass cleaning rod and cut it off at the appropriate length with a hacksaw. I threaded on a 7.62x39mm chamber brush (key is oversized in the neck area), chucked the cut-off cleaning rod in a DeWalt drill, stuck it in the chamber, and spun it at high speed until I was sure the carbon ring was gone. That took care of it and as long as I gave the neck/throat a bit of extra attention during my normal cleaning interval (100 - 300 rounds) it didn't come back again. I got 1500+ more accurate rounds out of that barrel on top of what it had when I was ready to trash it.
I cleaned and soaked it pretty thoroughly with C4 & then short stroked the throat with JB bore paste, re-measured length-to-lands and it was back out where I expected it to be. I brought the powder charge back up to the original load (30.3 gr Varget) and accuracy was back!!!... for about 30 rounds... and the carbon ring was already creeping back! Best guess is that I had let it go for so long and get so hard & established that the JB and C4 had only knocked it down a little bit, but not removed it.
Anyway, the point I was getting at is that out of frustration (and because the barrel was pretty much a tomato stake with that carbon ring) I took its removal to the next level. I took a cheap brass cleaning rod and cut it off at the appropriate length with a hacksaw. I threaded on a 7.62x39mm chamber brush (key is oversized in the neck area), chucked the cut-off cleaning rod in a DeWalt drill, stuck it in the chamber, and spun it at high speed until I was sure the carbon ring was gone. That took care of it and as long as I gave the neck/throat a bit of extra attention during my normal cleaning interval (100 - 300 rounds) it didn't come back again. I got 1500+ more accurate rounds out of that barrel on top of what it had when I was ready to trash it.
Also bought a borescope after that (Lyman) and keep a close eye on carbon rings in all of my rifles and work to keep them at bay. They're much easier to remove when caught early. So far VFG aggressive pellets with JB paste and/or gently spinning a slightly oversized copper brush in the neck/throat area (by hand) has worked the best at removing early-detected carbon rings, according to my borescope.
Wasn't all that impressed with CLR (I've tried it a few times). Not worth the risk of putting an acid into a barrel to me. I've soaked heavily fouled muzzle brakes and AR bolts in CLR verses soaking them in C4 and short-term CLR was faster, but on a longer soak the results looked the same to me. Interested in trying the slip 2000...
Wasn't all that impressed with CLR (I've tried it a few times). Not worth the risk of putting an acid into a barrel to me. I've soaked heavily fouled muzzle brakes and AR bolts in CLR verses soaking them in C4 and short-term CLR was faster, but on a longer soak the results looked the same to me. Interested in trying the slip 2000...
Friend of mine has a borescope that i can borrow. I'm going to let him have a look at it. Whilst shooting today i pulled a round and had a ring around the bullet again. Not running them into the lands as i've measured again. So evidently i'm thinking either the breaching ring is part of the issue or the more likely issue is i just knocked down the carbon ring. My brownells order with the pellets and such hasn't shipped yet. I've got a match in two weeks and my friend should be able to get it out as he has all the supplies. Did have some solid chrono results today found a great node with varget.
Had wild pressure spikes with my 4S and H1000 last year. Couldn't figure out what the hell was going on. Lost a bunch of brass due to the pressure. Figured it was something wrong with my loading. Found out about carbon rings. Bought the Lyman borescope and found the problem. Well worth the investment.
Well, I found one Sunday at the end of a match, I had a round chambered, when it was called, and when I ejected the round, it had a ring on it clear as day. I already ordered some of the aggressive pellets from Brownells (as I couldn't find them offered anywhere else, including Amazon). This was a couple weeks ago, but they are not in stock, so are back-ordered. Had to order the male threaded jag from Amazon, since Brownells only offered a female version of it. Anyway, for now, I'll have to do the best I can without them.
Sorry for the giant pictures. It seems that it's either that or thumbnail size.
Sorry for the giant pictures. It seems that it's either that or thumbnail size.
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Good pics! In a pinch or just as good as pellets is an oversize bore mop soaked with your favorite recipe,
I'll see if I have one that will fit. I plan on soaking it good first, with a mop or homemade swabs. Maybe overnight.
I guess that it was time for the barrel to get a good thorough cleaning anyway. It has about 1600 rounds on it and has only received cursory cleaning now and then. So I cannot blame anything except my own practices.
While I am at it, I believe I will soak the suppressor overnight too. I'd guess that it has a few extra ounces on it at this point.
When I get all done, I may have to check and see if the load still works in a clean barrel with a clean suppressor, lol. At the least, I'll make sure the velocity hasn't changed.
I guess that it was time for the barrel to get a good thorough cleaning anyway. It has about 1600 rounds on it and has only received cursory cleaning now and then. So I cannot blame anything except my own practices.
While I am at it, I believe I will soak the suppressor overnight too. I'd guess that it has a few extra ounces on it at this point.
When I get all done, I may have to check and see if the load still works in a clean barrel with a clean suppressor, lol. At the least, I'll make sure the velocity hasn't changed.
They've got them back in stock. I didn't get mine in before i had to get back to the Med Center. Let a friend of mine have at it. He took it to Deep South Tactical and let David look through with a bore scope it is clean. Had a terrible carbon ring in it.
They have them back in stock BTW. Wondering if i should go ahead and get some of the aggressive pellets too.
https://www.brownells.com/aspx/search/productdetail.aspx?sid=33148&pid=13839
They have them back in stock BTW. Wondering if i should go ahead and get some of the aggressive pellets too.
https://www.brownells.com/aspx/search/productdetail.aspx?sid=33148&pid=13839
I should get mine soon then, I hope. I ordered them on back-order. I received the rest of my order already.
So, you did all of that scrubbing and the carbon ring was still there? Is the smith going to take care of it or are you? And how? Inquiring minds and all that, you know...
So, you did all of that scrubbing and the carbon ring was still there? Is the smith going to take care of it or are you? And how? Inquiring minds and all that, you know...
I guess it was still there i had no means of checking it. It must've been pretty bad, truthfully was probably 500rds suppressed with maybe a run of hoppes through it at one point. I a friend of mine have it since i had to go back to Jackson, he's here, and i don't have all my rods and stuff here. The match is this weekend, he cleaned it with the pellets and then took it to David's to use the bore scope to check.
Here's the pics he sent me. This was the first patch i guess after scrubbing.
Not sure if I can contribute here, I'm looking to learn a bit myself. My 6x47 Lapua was chambered by Josh at PVA, we had a conversation about this subject. He recommended using fuel injector cleaner from any automotive store, to knock down carbon rings. Josh said by doing this regularly, he's seeing barrel life increases with the fast 6's. I can't answer to that, I'm still new to the 6mm's. I can say I tried it on the crown where I had significant carbon build up after 100 rounds suppressed. A little scrubbing with what ever fuel injector cleaner I got, definitely defeated it. I'm curious to see what members of the hide say? I'm still a bit nervous to put that in my Bartlein.
Has anyone tried Naphtha? It's a common ingredient in some popular FI cleaners, and can be had for much cheaper (Lowes - paint section)
You're kidding, right? CLR crushes carbon like a madman.
I’m the one that cleaned the rifle in the picture, all that was used was CLR so if it doesn’t work on carbon why are the patches black? I clean my suppressor with CLR it eats carbon up better than anything I’ve tried.
CLR works like a champ on carbon
Carb cleaner
Fuel Injector Cleaner
Both of them are EXCELLENT at cutting carbon rings in the throat.
Don't get either on plastic bits but if you use the buffalo bore pellets above, shove it into the throat and soak it with carb cleaner the carbon ring will wipe out in a very short period. No abrasive scrubbing or anything.
I don't use the pellets, I wrap a nylon brush with a little patch of tshirt and do the same thing.
I've yet to see a small town that doesn't have an auto parts store, even the place my grandmother lives with under 500 people in the entire voting base. All the auto parts stores carry the cleaners I mentioned above.
Fuel Injector Cleaner
Both of them are EXCELLENT at cutting carbon rings in the throat.
Don't get either on plastic bits but if you use the buffalo bore pellets above, shove it into the throat and soak it with carb cleaner the carbon ring will wipe out in a very short period. No abrasive scrubbing or anything.
I don't use the pellets, I wrap a nylon brush with a little patch of tshirt and do the same thing.
I've yet to see a small town that doesn't have an auto parts store, even the place my grandmother lives with under 500 people in the entire voting base. All the auto parts stores carry the cleaners I mentioned above.
I’m with Josh.I have used carb cleaner on my rifles for years,never had a issue,never tried fuel injector cleaner but I will.I have also used bore techs carbon cleaner with good results.
Carb cleaner works; it's what I used to use on my SAW when the CG inspection was coming up (and those pigs would get caked and baked with carbon). That stuff (carb cleaner in an aerosol can) would cut through carbon pretty quick, and just leave a light film behind. I'd drag the whole machine gun into the shower and hose it off with hot water, then dry, lube, and call it good. On days where the unit was doing weapons cleaning, the whole damned barracks smelled like carb cleaner (armory was literally two buildings over, so everyone just took their weapons back to the barracks for cleaning).
Nothing new here about carb cleaner. The old is new again I guess...
Nothing new here about carb cleaner. The old is new again I guess...
I cleaned my 6.5 Bartlein with patch out wipe out and the accelerator and patches were clean. I put a CLR soaked patch on a nylon 6.5 brush and it came out black. I did it a few more times and then ran wipe out until it was clean.
The last time I shot I was having some unexplained pressure signs, now I know what it was. I am running Re16 suppressed.
The last time I shot I was having some unexplained pressure signs, now I know what it was. I am running Re16 suppressed.
I tried carb cleaner on two occasion and it never worked out and they leave a lubrification film too...
I use the carbon destroyer form Spartan and it worked sometime on light carbon ring but not on nasty ones. Iosso paste with VFG pellet work really well and simichrome also.
The break cleaners don't leave a film.
Is that spray stuff of liquid? What was josh procedure?
I think guys are definitely on to something when they talk about carbon rings and barrel life. Clearly, Josh thinks it is an issue. Joe Hendricks that developed the 6 comp match suggested cleaning every 200-400 rounds with JB Bore Paste. He said that and using H1000 was the key to long barrel life in the 6 comp match or the 243. I have been running a 243 Ackley for 1700 rounds now using H1000 and cleaning the throat with JB Bore Paste every 200 rounds. The gun still shoots very well (.5 moa), and I have not seen any detectable velocity drop. I do not have a good chronograph, so I am going off my dope. I have not had to adjust anything yet out to 1000 yds which is as far as I typically get a chance to shoot. It seems as though there is some agreement that carbon rings can be a real issue in making a barrel appear to be shot out. I definitely need to invest in one of the Lyman bore scopes.
I'm making an assumption here, a carbon ring and carbon buildup in the throat area are 2 diff issues. A carbon ring forms in the area where the reamer steps from the neck part of the case to the area we call freebore. A lot of factors can contribute to this, short brass, unburned powder, or insufficient burns etc....
Carbon buildup in front of the throat creates a little bit different set of issues.
So, to clear this up for me, what would you call the carbon 'ring' that showed itself on my bullets in the picture above. By your definition, it is not right at the transition of the neck and the freebore, but it is a ring of carbon build up that is before the lands in the freebore, roughly where the ogive sits. This creates a false jammed characteristic, which increases pressure at the chamber.
When matters puzzle me, I reexamine my assumptions.
One assumption could be that the bullets being seated to an existing load spec and getting stuck in a throat where they previously passed w/o issue are properly to spec.
Maybe if the bullets were mic'd, something interesting might turn up.
Greg
One assumption could be that the bullets being seated to an existing load spec and getting stuck in a throat where they previously passed w/o issue are properly to spec.
Maybe if the bullets were mic'd, something interesting might turn up.
Greg
Were you able to chamber the rd? Sometimes just having a couple bullets seated deeper in the case will blow what you have out. It's leaving a ring on your bullet for sure, if you were to borescope it, would it look like a ring, or just the start of build up.
I have a hawkeye scope, I've never actually seen a ring in the throat.
I mic both my bullets and my base to ogive as I prep and load. Maybe the lands moved closer to the chamber...
Just so that you are aware, I spent quite a bit of time working to remove the carbon that actually existed, using a combination of many of the magic solutions suggested. Surprise, surprise, none of them worked as easily for me as perhaps expected. The carbon is now gone, I no longer have the indicator ring showing on a loaded round, and the pressure signs are gone.
Same batch of loaded rounds used.
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Yes, that round in the picture and others like it were fully chambered and then removed. Maybe what occurred isn't called a ring, but I surely creates a ring shaped mark on the bullet where it is constricting the bullet. So perhaps it's a matter of semantics, but this was most certainly a "ring" of carbon in the throat. The picture is of pretty good resolution, so it's easy to see that this is not markings from the lands (unless, as above, I'm experiencing the previously unknown advancing of the lands).
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You're right, definitely in the freebore area behind the rifling, the lands would contact the bullet on the slope of it's nose. Could be in the transition area I spoke of and carried forward. As you said in a post, it was not easy to clean and I bet not, lolYes, that round in the picture and others like it were fully chambered and then removed. Maybe what occurred isn't called a ring, but I surely creates a ring shaped mark on the bullet where it is constricting the bullet. So perhaps it's a matter of semantics, but this was most certainly a "ring" of carbon in the throat. The picture is of pretty good resolution, so it's easy to see that this is not markings from the lands (unless, as above, I'm experiencing the previously unknown advancing of the lands).
I do know you want it all out to start fresh, just aggravating it and leaving some in just speeds up the return process, my favorite is Boretech C4, and brush 2 calibers bigger, chucked up in a cordless drill. May have to cut a decent rod,, or a screw together.
AR's are notorious for this shit, but 6mm's are in a league of their own if conditions are ripe.
Ha e a link to the amazon piece?
I just did a total clean on my 6.5x47. Shooting 140 hybrid and Varget. Ran 20 rounds thru it Friday and picked up some speed. Average for the session was 2836 fps
Wow! That was 8 months ago. I just did a bit of amazon searching for you though. I’m not sure if it was this one:
https://www.amazon.com/Tipton-Clean...eaning+jag&dpPl=1&dpID=31UceCCk4oL&ref=plSrch
Edit: I just realized that the Tipton jags are new and not all available yet, so it couldn’t have been that one. So I searched some more and found this, which I believe is what I have:
https://www.amazon.com/Pro-Shot-Ada...i=AC_SX236_SY340_QL65&keywords=vfg+pellet+jag
Thanks.
