Looking into my spare barrel with borescope

[Rcher]

So, I ordered spare barrel (just in case) for CM9 Gen2 from SAR-USA.COM.
Finally had chance to test on a range, it did fit my gun perfect and accuracy was in par with the original barrel. No issues found.

I shot only 100 rounds and was surprised how dirty the barrel was after inspecting it with borescope.
Even soaked it in Hoppes 9 for a couple of days and did clean very well till getting white patches.

The barrel still looks ugly it has rough black colored build-up. I don't know if it is carbon or something else (I did clean barrel before shooting, so it should not be factory grease).
So, what is it and how to remove it? Could it be that barrel itself is rough enough (not polished) because of poor machining.


 https://youtu.be/yeGF2T4XkSM

[SI VIS PACEM PARRABELLUM]

You might pick up some JB bore paste and try cleaning it out with that. I find it gets the crud out that Hoppes won't touch.

[M1A4ME]

You might pick up some JB bore paste and try cleaning it out with that. I find it gets the crud out that Hoppes won't touch.

I bought a couple 4" Shield Plus 9MM barrels earlier this year.  Absolutely nasty inside.  No idea what that stuff was.  Hoppes#9, carb cleaner, brushes, patches, copper remover, lead remover, etc. didn't touch that stuff.  Bought my first ever little jar of JB Bore paste and after some paste, patches and elbow grease finally started getting clean patches.

I normally don't use jags for bore cleaning but in a pistol, between the short rod and shorter stroke that's what I used with running the JBs through the barrels.  It wasn't quick but it removed whatever that crud was and shined up the inside of the barrel.

[Joe L]

The lands look good but there is still some stuff in the grooves.  The chamber end looks like there is still some carbon there also.  I would also try the JB Bore paste on a patch wrapped around a brush. 

What bullets are you using? 

The problem I have with a borescope is that it can make a mountain out of a mole hill.  I have one on my computer desk and one in the shop and I've given up trying to get down to bare metal every time I clean a barrel.  But I usually don't see the flakes I see in your video either.  I've used Kroil and Bore-Tech C4 (my current favorite as of a week ago) to get the carbon out, but any lead or copper takes the paste and a brush. 

I will clean my P-10F barrel this morning, and may post a borescope video for comparison. 

Joe L

[Crawl]

Make sure you're not doing this do melonite treated barrels.

[Joe L]

Here is a borescope video of a factory P-10C barrel and then a Primary Machine P-10F barrel.  Both after some solvent patches, no brushes or JB Bore Paste.  In other words, after a light cleaning to get most of the carbon out. 

https://youtu.be/yTTnhY8JnhE

The P-10C barrel is a little rough at the chamber end so I will hit it with some bore paste this afternoon, and will probably do the same with the F barrel, but it looks pretty good to me. 

The white blob is Kleenex on the end of a cleaning rod section that I use as a reflector for the straight on borescope shots.  It is not necessary when using the angle adapter.  The straight on bore shots give a better idea of how thick any debris is in the barrel and it is also easier to see carbon in the edges of the grooves and deposits at the chamber end. 

I might post another video after I "deep clean" the barrels later today.  Maybe. 

Joe

[Rcher]

The lands look good but there is still some stuff in the grooves.  The chamber end looks like there is still some carbon there also.  I would also try the JB Bore paste on a patch wrapped around a brush. 

Will Flitz metal polish paste work as well?

What bullets are you using? 

My reloads - copper-plated Berry's.

The problem I have with a borescope is that it can make a mountain out of a mole hill.  I have one on my computer desk and one in the shop and I've given up trying to get down to bare metal every time I clean a barrel.  But I usually don't see the flakes I see in your video either.  I've used Kroil and Bore-Tech C4 (my current favorite as of a week ago) to get the carbon out, but any lead or copper takes the paste and a brush. 

I will clean my P-10F barrel this morning, and may post a borescope video for comparison. 

Joe L

Yes, these flakes concerns me - never seen them in my other barrels. Usually I see copper residue but not carbon. I will try other solvents like Balistol, M-Pro, etc... before trying Flitz (last resort).

[Joe L]

I've also used some abrasive pellets with JB Bore Paste smeared on them with good results.  That is what I did today on the two barrels in the previous video above.  Took about 15 minutes in the shop.  These barrels are ready to shoot now.  May take a while for YouTube to finish processing the video.

https://youtu.be/cS4okkIWnVA

There is still a tiny bit of carbon in the groove side wall area near the muzzle on the F barrel, probably because I didn't use a brush when solvent cleaning.  Patches and pellets will get the middle of the grooves cleaned up but they won't conform to the edges well enough to get good contact near and in the groove wall. 

I am done until I shoot the pistols again.  Next is to light clean the .308 Savage barrel, which is shooting really well right now.  It just needs some carbon removal and some oil.

Joe L

[RSR]

FWIW, carbon is best dissolved by water-based cleaners, and Hoppes #9 is now weaksauce vs its former formulation, which IIRC was more geared towards copper and lead fouling than carbon.

And personally, I don't own a borescope so as to not trigger the OCD...  If your concerns require a borescope, they're probably not actually worth worrying about...  Bright and shiny to the eye holding to a window or light after cleaning with copper or poly brush should be the benchmark IMO.  YMMV.

Lastly, Flitz will remove material, I'd stay away but you're welcome to bubba your own firearms.  Good luck!

[Rcher]

Well, it's just my spare barrel with cost of $60, so I'd give a try. And if I destroy it - I can always order new.
(And instead of black barrel I will order stainless steel.)

Ok, I recalled that I have ultrasonic cleaner and looked for the videos on how to clean carbon with it. Was inspired by this video, an idea to safely use any solvents, even "flammable" gasoline and to make things done.

https://www.youtube.com/watch?v=BTN7-C72eHA

[Rcher]

My "safe" cleaning process. Ultrasonic tank is filled with water, prescription jar with barrel inside is filled with cleaner (gasoline in this case).

https://youtu.be/2m9M9H84dPI

[Rcher]

So, I tried ultrasonic cleaning with four different solvents:

(1) Simple Green, 1/3, 140F, 20 minutes
Results: https://youtu.be/_bPbE2VoxAA

(2) Balistol Milk, 1/10, 122F, 20 minutes
Results: https://youtu.be/KUN5vpjTn9s

(3) Mineral Spirits, 1/1, 102F, 20 minutes
Results: https://youtu.be/TzmHLdC2t_s

(4) Gasoline, 1/1, 70F, 10 minutes
Results: https://youtu.be/D3DEKvOyL-k

[Rcher]

At this point I'm not convinced that the residue is carbon build-up. Possible some rust (as I also see dark reddish flakes) or something else.
I think I'm done with ultrasonic cleaning at this stage, it definitely helps with my BCGs (bolt looks like new), but not with this stubborn residue.

I plan to try other options which are claimed to have good results both with rust and carbon: Kroil / FreeAll and finally JB Paste.

[M1A4ME]

At this point I'm not convinced that the residue is carbon build-up. Possible some rust (as I also see dark reddish flakes) or something else.
I think I'm done with ultrasonic cleaning at this stage, it definitely helps with my BCGs (bolt looks like new), but not with this stubborn residue.

I plan to try other options which are claimed to have good results both with rust and carbon: Kroil / FreeAll and finally JB Paste.

One idea on rust.  There's some stuff out there called Fluid Film.  Biodegradable, non toxic, the whole 9 yds.  Been around for years.  The guys on the Ford Truck Forum swear by it for stopping your truck/car from rusting in the winter road salt, but, the description also says it penetrates existing rust all the way to the metal beneath it and stop further corrosion.

So, I wonder if it penetrates to the bare metal below the rust and seals it off would any real rust in a barrel then easily come out with some brushing/patching after a few hours of sitting on the shelf after coating the inside of the barrel with Fluid Film?

Or, the old fashion way would be to smear some naval jelly inside the barrel (be careful to keep it off the outside finish, I know from experience it used to take parkerizing off metal) and let it sit before flushing it out and inspecting the barrel before putting a coat of oil in there to keep it from further rusting.

[Motorcop]

I think a good choice might be to wrap a few strands of copper from a Chore Boy pad around a metal brush and pass it thru the barrel with some Kroil on the brush.  Just make sure the copper is not actually copper washed steel.  This method works very well for cleaning lead and carbon out of badly fouled barrels and may work in this instance.  Don't overload the brush with it though.  There is another product that is similar to the Chore Boy one, but I can't think of the name right now.  It's called Big.45 or something similar, but I have never used it.

Rick H.