Home Forums Hunting & Shooting Ask The Gunwriters Hard powder/carbon removal

I posted this on the 'Teslong' thread but thought it might be interesting enough to follow on it's own. Or maybe not. Anyway.....

This is a barrel with some hard powder/carbon that's accumulated in the space between the end of the chamber neck portion and the end of the case mouth that needs to be removed.

The first pic is the area after being cleaned normally. The hard powder is the dark band on the lower right. The grey area ahead of it is the 45 degree bevel as the chamber neck transitions to the throat/free bore/leade area. You can see that that bevel has been well cleaned by the normal cleaning process. The angle makes that bevel appear quite a bit wider than it really is.



To get after the hard powder, I use a bronze brush that's one caliber larger that the bore size. This is a .30, so a .338 brush is used. The brush goes on a short pistol cleaning rod and the leading edge of the brush is loaded with JB Bore Paste. The brush is gently inserted until you feel it stop at the end of the neck. Mark the cleaning rod to keep it in this spot. Make 10-12 complete turns of the brush in a clockwise direction. Watch the mark you made and make sure you're not shoving the brush into the bore. Remove the brush using a clockwise rotation. Clean the chamber with a bore mop and push a wet patch down the barrel followed by a dry one. Check your progress via the Teslong. Depending on what you see, you can adjust how many rotations of the brush you give it. About 30 is where the JB breaks down and gets less effective. Clean the brush with some spray brake cleaner, etc. Repeat as needed until it's gone.

Second pic is done as described. After 12 turns, the hard powder is already about half gone.



How much a barrel is going to need depends on a lot of things. The amount of gap between the end of the case neck and the end of the chamber is the primary factor followed by neck clearance. Obviously a chamber with .008 neck clearance is going to load the area quite a bit more than a chamber with .003 neck clearance. Add in case volume and powder characteristics and it's easy how some combinations can get to be a mess in this area. The combination of big case volume, large neck clearance, necks way to short for the chamber and bunch of slower burning power and lower charge weights is about the worst.

Good shootin' -Al

Al,

Is there any difference in accuracy, pre vs post treatment?

My question, is this strictly a borescope issue or a functional issue?

Asking for a friend, don’t ya know.

DF

Al,
Do you use any of the carbon remover products prior to the JB Compound?

Good info Al, thanks for posting.

It can be both...depends.

I load for a buddy that has a sporter barrel M77 in 25-06. He's a hunter...not a range guy except to sight it in before hunting season. He's horrible about cleaning so once a year, it finds it's way to my place for a good cleaning and reloading of ammo. The last time, I stuck a new Nosler 100 gr. BTip in the neck of a fired case...and it wouldn't go in. With a 10X loupe, you could see the neck was pulled in right at the very end. The Hawkeye bore scope confirmed a huge amount of hard powder at the very end of the neck area of the case...enough to prevent complete expansion of the neck when firing. I treated it with a 6.5 brush and after some effort it was clean. Fired cases would then let a bullet drop right in.

Good shootin' -Al

Awesome info!!! I do this every 300 rounds. Would it be more beneficial to do this everytime?

Thanks Al

No, I don't. I end up going in there with JB or a brush, anyway. Iosso also works. It's a bit more aggressive than JB but it does a nice job. The beauty of JB is that it breaks down and you can't really do any harm.

Good shootin' -Al

It really depends on the individual situation.

Interestingly, I've found that if there's any left at all, the resulting accumulation happens much faster than when it's cleaned to bare steel. I think the burned powder 'grabs' on to the remnants of the hard powder and builds on top of it. That's not to say that hard powder accumulates in a nice even thickness once the metal is completely clean to start with...far from it. But it's worse when any remaining bits aren't completely removed.

Putting a case in the chamber and observing what's going on right at the end of the neck area can be most revealing.

Good shootin' -Al

Al- what is your take on the Sinclair Chamber Length Gages and potentially letting cases exceed book max lengths in? Thank you.

Just treated it again with 20 spins. This is the same area...coming along nicely.



Good shootin' -Al

Good info, Al.

Thanks for posting.

DF

I use them all the time....every hand loader should have them. Finding your chambers actually length, is very important. Once you know that, the case can be trimmed accordingly. For example, I have a Savage single shot 112J in 25-06 with the factory barrel. The actual chamber length is .040 longer than the max. length per SAMMI. When I got it, there was so much hard powder in the end of the chamber....didn't think I'd ever get it all out! I just let the necks grow to fit the chamber. Even on a custom chamber, it's good to know and not trust the chamber length to the reamer specs. Jot down the length after checking it and toss it in the die box or your ammo box for reference.

I load for stuff from hunting rigs to competition guns....here's a few of the ones I use. You can also have the reamer used on a custom build put into a piece of aluminum round and mill half of it away. This gives a very good visual of where the neck is at.

Good shootin' -Al

Thank you for this thread. I had this issue with a tight-chambered 300WM that I shot a lot. Erratic pressure/accuracy left be chasing my tail until I realized that the mouth of the cases were being crimped upon firing. Pushing a bullet in a fired case was a tight fit. I'm sure trimming to minimum case length was a contributing factor. At the time I thought I would be helping the problem, did not realize hard carbon build-up was a thing. Coming at the problem from a novice standpoint, it took me quite a while (and finally a Teslong borescope) to diagnose and cure. I finally fixed it by the same method after trying others. JB or Iosso and a brush one size over was the cure. I was not able to find a lot of info on this issue online - this is the first I have seen in explained well.

All better now. The line you see is a bronze brush bristle.

This one took me 10 sessions to get cleaned up....the last bits were stubborn. It's a used gun I just purchased and I doubt it's ever been done before. Hard to say how many rounds down the barrel. It's a small capacity .30 (30BR) with a .330 neck and necks that measure .328 across the pressure ring. With H4198 at around 65,000 PSI, it's about as clean burning and efficient setup that there is. It's probably the Best Case scenario...which is another reason I thought it may be of interest.

The rate of build up and amount in something like this will be quite a bit less than a big cased deal with a bunch of charcoal in there for powder and big neck clearances.

I'd add that if you do this, don't grab your cordless Dewalt and decide to spin the beejeezus out of the brush to get it done quicker. JB breaks down rapidly and all you'll do is reduce the JB on the brush to a big blop of grease and wonder why you're not making progress. The grease is the carrier for the diatomaceous earth that's the abrasive medium in JB. Can't speak to Iosso.

During this, I also tested some carbon treatment that's supposed to magically dissolve carbon. To believe the adds for this stuff, it'll make your 401K healthier, butter your toast and you'll never have to balance your checkbook again. The best I can say is that I liked the smell as I'm a citrus guy. Shooters raving about this product clearly have no means to check their work. It's on the shelf along with all the other carbon killer miracles.

Abrasives are what works for hard powder fouling. Period.

Good shootin' -Al

Now I'm going to have to pull out the Teslong and do some checking.
Thanks for posting this.

Doesn’t Lou Murdica say somewhere that he uses Iosso on a brush powered by a drill?

Tag

Yes, he does. Not sure what he's using for a brush, etc.

Thanks Al much appreciated! It's an important topic that rarely gets covered

Trystan

the chamber length gauges I think are great. it's of my opinion the more brass fills the chamber the less area there is to get carbon filled..

There are some YouTubers using CLR to remove carbon from their firearms, most that I have seen are using it on SS. I tried it on a Ruger American that I had, that I thought that I got all of it out of the barrel, but 1 drip ran down the crown and hung onto the bottom of the barrel, while it was it a cleaning cradle. Bore Tech makes a Carbon Remover that I've had no problems with, that I use with the Bore Tech Eliminator.