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Penetrating Oil For Barrel Cleaning

CK1.0

\m/ SLAYER \m/
Full Member
Minuteman
Sep 2, 2020
2,322
2,746
Nashville
Until a few days ago my views on barrel cleaning could be summed up as Bore Tech Eliminator, nylon brushes, cotton patches, that's it, no abrasives, ever. I only pulled out the borescope if I needed it to diagnose a problem, otherwise, it stayed in its box on a shelf.

I had arrived at this ethos due to seeing and hearing many guys go bananas with their barrel-cleaning regimes to the point where it was arguable that they were doing more harm than good. I'd been completely turned off from getting too deep in the weeds with barrel cleaning after seeing too many guys spend more time on getting good with a borescope than actually shooting.

Well, you can teach an old dog new tricks and I've evolved on the subject.

I was talking to someone I trust about it whether abrasives were a good/bad idea, etc and he made a very impactful statement: what one chooses to use as far as cleaning doesn't even really matter that much, but, the fact that borescopes are so cheap now is what is really the thing.

His point was: now that we all can see what we're doing, we should all be able to tell whether we're doing good or fucking things up, just by looking and checking. I hadn't thought of it like that, but that made sense to me.

Here's a 6CM barrel that had 2300 rounds on it when I pulled it, I used a fairly large jump and loaded 0.100" off the lands the whole time, and used a mild load making ~2900fps. Measuring the lands/throat, it barely moved, I lost something stupid like ~3 thou (almost too little to measure).

I figured it died because of fire-cracking... but now I'm not so sure... now I think it stopped shooting because of heavy carbon buildup.

I decided to put the borescope to use and try using penetrating oil as I had heard good things about it breaking hard carbon loose...

Anyhow, if pictures are worth 1000 words, here are "10,000 words". This is after soaking in Eliminator for a couple of days (didn't do a whole lot honestly), then ~30 minutes with penetrating oil, a little Iosso, and a couple of bronze brushes ->

Before:

Photo on 3-19-23 at 2.32 PM #2.jpgPhoto on 3-19-23 at 2.32 PM #3.jpgPhoto on 3-19-23 at 2.33 PM.jpgPhoto on 3-19-23 at 2.33 PM #2.jpgPhoto on 3-19-23 at 2.33 PM #3.jpg

After:

Photo on 3-19-23 at 4.39 PM.jpgPhoto on 3-19-23 at 4.39 PM #2.jpgPhoto on 3-19-23 at 4.40 PM.jpgPhoto on 3-19-23 at 4.41 PM.jpgPhoto on 3-19-23 at 4.41 PM #2.jpg

I'm going to spin the barrel back on and see how it shoots in the next week or two... but it looks like there might be more life in it yet.

If it shoots, it'll be good news because I've got another barrel with 2200rds on it that looks just like this one that maybe isn't a tomato stake just yet either... but I think if I end up hitting the next one I'm going to let it soak with the penetrating oil for a couple of days instead of the Eliminator because the penetrating oil seems to do most of the heavy lifting.

I was kind of amazed at how well, and how fast the penetrating oil worked while following along with the borescope, I think it's definitely worth giving a try if you find yourself dealing with heavy carbon. FWIW I used Liquid Wrench Penetrating Oil (yellow and white can), but went to the store looking for Free-All which I've heard is good too and I might try at some point.
 
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That looks really good for that many rounds. Here's a 28 Nosler throat just north of 500 rounds a customer brought in. I cleaned it with Barnes CR10 and a nylon brush to get a good look at the bore condition. The barrel is finished, the firecracking is at least that bad for 3 more inches.

Photo_20230227162052.jpg
 
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That looks really good for that many rounds. Here's a 28 Nosler throat just north of 500 rounds a customer brought in. I cleaned it with Barnes CR10 and a nylon brush to get a good look at the bore condition. The barrel is finished, the firecracking is at least that bad for 3 more inches.

View attachment 8101019

Part of me is wondering if mine looks good because I had kept it "protected" by a layer of carbon for 2300rds? 😜

Seriously, the barrel had never seen any abrasives and maybe that's part of why it's in good shape, IDK? I cleaned it every ~200 rounds, and it kept shooting well right up until it didn't... but I only ever used Bore Tech Eliminator, patches, and their nylon brushes (probably didn't change them as often as I should have either).

I think from now on, going forward, I'm going to let the borescope tell me what to do. No more, no less, not necessarily bare metal, but as clean as possible without fucking anything up or having it take all day.

One thing is certain, I'm a convert from being stingy/stupid with bore brushes and will be throwing them out after a single use, and using a new one every cleaning from now on, that's for sure.
 
I use kroil or butches bore shine. I have montana extreme for copper but rarely break that out, also you have to be seriously careful with it or it will kill you
 
CK
I think your barrel is toast. I would be very surprised if it shoots well at this point. Look at the edges of the lands, when pieces are missing and rough looking I don't think there is any going back.
 
CK
I think your barrel is toast. I would be very surprised if it shoots well at this point. Look at the edges of the lands, when pieces are missing and rough looking I don't think there is any going back.

You might be correct, in fact, I tend to lean that way myself, but, I pulled so much carbon out of it that it might be worth a try just to satisfy my curiosity... 🤪

It was already on the trash heap and seriously going to become a tomato stake... but it isn't a huge deal to swap barrels for me just to see, maybe 15 minutes to pull the BA swap barrels and drop the BA back in, just depends on if I have the time and how bored and/or lazy I am.

I have the one I put 30mins into, and another one I hadn't touched yet since pulling it, plugged with earplugs, and filled/soaking in penetrating oil. I plan to put another 10-15mins into the one I was already working on in the next few days, just a quick brush and patch out, and depending on what I see, you might see me at the range with it, IDK yet lol.

tempImage8eYzZH.png
 
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You might be correct, in fact, I tend to lean that way myself, but, I pulled so much carbon out of it that it might be worth a try just to satisfy my curiosity... 🤪

It was already on the trash heap and seriously going to become a tomato stake... but it isn't a huge deal to swap barrels for me just to see, maybe 15 minutes to pull the BA swap barrels and drop the BA back in, just depends on if I have the time and how bored and/or lazy I am.

I have the one I put 30mins into, and another one I hadn't touched yet since pulling it, plugged with earplugs, and filled/soaking in penetrating oil. I plan to put another 10-15mins into the one I was already working on in the next few days, just a quick brush and patch out, and depending on what I see, you might see me at the range with it, IDK yet lol.

View attachment 8101442
It's worth a shot for sure. Even if they can be turned into a hunting barrel you have something for your effort.

I have a Proof barrel that is kind of in the same condition, it's clean but I fought that barrel for 6 months and couldn't bring it back to where I was going to be happy with it. It will hold 3/4 to 1 MOA but that doesn't do anything for me.
 
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It's worth a shot for sure. Even if they can be turned into a hunting barrel you have something for your effort.

I have a Proof barrel that is kind of in the same condition, it's clean but I fought that barrel for 6 months and couldn't bring it back to where I was going to be happy with it. It will hold 3/4 to 1 MOA but that doesn't do anything for me.
Both of these barrels (SS 26" Proofs) would hammer (SEGR's 33% IPSC at 750 was no problem) until one day, with both, they suddenly lost ~100fps and fell off a cliff... I kind of want to see if they died a natural death or if I just let them get too dirty by not cleaning them aggressively enough?

I am shooting a 6GT now and don't have more than ~500-1000 LRP's left, but it might be a fun way to use them up I guess.
 
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Shooter choice mc-7 by chance?
Yes, I've been told that the Kroil will take the SC with it as it penetrates small cracks and the like.

I've used it and not seen any better results that from using other products also.

How to clean a barrel is sort of the rifle version of the eternal trap shooter's thread...."7 & 1/2 or 8's"?

LOL
 
An gotcha. Well. I may try it out. I have a can of kroil the nozzle busted off of. And a bunch of SC because I normally use Boretech eliminator. But I’m out so I’m willing to try something new.
 
An gotcha. Well. I may try it out. I have a can of kroil the nozzle busted off of. And a bunch of SC because I normally use Boretech eliminator. But I’m out so I’m willing to try something new.
Give it a shot, my friend. It won’t hurt anything and you have the fixing’s.
 
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Free-All sucks. Break free CLP whips its ass. That “Winning in the Wind” guy is a liar and his finger didn’t smell like strawberries either…
 
May want to measure your distance to lands now. 2300rds isn't too many to be smoked but it doesn't look like it.
 
First patch is a Kroll soaked one. Usually let it set for a bit before moving to cleaning solvents. It's also the last thing I do, followed by dry patches. Satisfies my OCD....
 
May want to measure your distance to lands now. 2300rds isn't too many to be smoked but it doesn't look like it.

I agree. If I end up deciding to spin it back on, the first thing I'll do is measure the throat/lands and see what I get... I have notes from when the barrel was new to compare to.

I suspect the lands have eroded more than I previously thought (judging by the metric shit ton of carbon I pulled out so far), but IDK, I'm kind of wondering if all that carbon protected it from wear in some way?

The barrel shot great the whole 2300rds until it died, so over that span of time, just using Eliminator alone worked well enough. But, I thought the Eliminator was doing a lot more and removing more carbon than it actually was, so IDK.
 
I've seen barrels with missing rifling not shoot, but yours is no wear near that. I also seen a 270 WBY ballistics lab barrel with 4 inches of it's throat missing shoot well. It needed work with JB whenever the throat got rough and the velocity was off but it shot half moa or better. I'd give that barrel a try and if it doesn't shoot work on it with some JB blue label and a tight fitting patch on a jag and a good bore guide.
 
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If you got 2300 accurate rounds out of a 6CM and didn’t have any carbon ring issues, then you were doing something right pre-boroscope.
 
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So here's the barrel I had already put ~30 minutes into, this time after a ~48 hour soak with the penetrating oil. I used a brand new bronze brush until it was worn some, then I wrapped a couple patches around it and used it with some Iosso. Finally, I pushed a couple of wet patches of Bore Tech Eliminator through and then dry patches.

I put ~10+ dry patches through and it was still showing a little black/carbon coming out, so I'm guessing the penetrating oil is still working a bit...

Anyways, I think it looks damn good and think it's worth giving a try, maybe there's life in it yet.

I have an unexpected off-day today so looks like I might start in on the other "dead" barrel I have soaking too.

Post-soak pics ->

freebore:

Photo on 3-22-23 at 10.50 AM #2.jpg

start of lands:

Start of lands.jpg

~1 inch from chamber:

1 inch out.jpg

~2 inches from chamber:

2 inches out.jpg

~4 inches from chamber:

4 inches out.jpg

~halfway between chamber/crown:

half.jpg

~1 inch from crown:

near crown.jpg


tempImageIjCt0B.png
 
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If your barrels are losing a lot of velocity they're probably shot out. They don't look horrible though. I know this goes against everything you believe in but you might want to try a seating depth test.
 
If your barrels are losing a lot of velocity they're probably shot out. They don't look horrible though. I know this goes against everything you believe in but you might want to try a seating depth test.

IDK, the barrel looks better than I expected, but I'm still a skeptic and will be unsurprised if it doesn't shoot and is still dead.

It doesn't go against anything for me to play with jump a bit, I'm a believer in finding a seating-depth/bullet-jump "zone" that one's bullets might seem to prefer. I'm just a total "heretic" once guys get into that OCW/node stuff. I just add as much powder as I need to get the speed I want and it miraculously works every time, so I might be caught in a Rick Sanchez "cosmic node" or something lol.

I don't currently have any 6CM rounds already loaded up, so when I load some I'll probably leave some long in order to play with seating depth a bit if I think it might help.

The problem for me will actually be if it shoots again... because then I'll have to wonder if it means I'm not cleaning enough, or does it mean I should keep on doing what I've been doing and only do a deep clean once the barrel feigns death ~2000rds?

If it'll print ~1/2" groups at 100 and under 6" at 750 yards, I'll call it back from the dead, but short of that, I'm not going to spend any more time on it.
 
Wipeout

the stuff is magical, spray and walk away. come back a couple hours later and your barrel looks brand new.

I'm interested to see if the carbon ring removal will help with accuracy. 2300 rnds is a lot too though
 
Wipeout

the stuff is magical, spray and walk away. come back a couple hours later and your barrel looks brand new.

I'm interested to see if the carbon ring removal will help with accuracy. 2300 rnds is a lot too though

I didn't have any carbon ring issues, the barrel shot normally until one day it didn't.

The Eliminator seems to take care of the copper and most of the carbon... and the penetrating oil and Iosso seem to take care of everything else.

What benefit might something like Wipeout have? This barrel is just sort of a cadaver so I guess I could try it...
 
I like Kroil and Shooters Choice cut 50/50. Some of that on a VFG pellet and cleaning is way easy.
I also love kroil, but you guys be careful with this stuff. I think it could be what contributed to the tumor I am currently at MD Anderson Cancer center with. Definitely use gloves and dont be ignorant like me.
 
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It's not the penetrating oil that did the cleaning....

It was the abrasive losso
 
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It's not the penetrating oil that did the cleaning....

It was the abrasive losso

Possibly. I'm not nearly as spooked by the abrasives now that I've become comfortable using the borescope to make sure that I'm not doing any harm.

I decided to swap the barrels today, rather than start cleaning on the other old barrel I have, seeing as though I don't really know if the first one I've cleaned up is actually back from the dead or not.

I took off a newish 6GT that has just over 600rds on it, and holy shit, it looks like crap (half of the reason I decided to give the old one a try).

This is after some Eliminator and nylon brush, a new bronze brush with penetrating oil, then a couple of patches with Iosso wrapped around the worn bronze brush... I didn't spend very long on it but I thought it'd look better than this, here are some pics from the chamber to the crown:

Photo on 3-22-23 at 2.03 PM.jpgPhoto on 3-22-23 at 2.03 PM #2.jpgPhoto on 3-22-23 at 2.03 PM #3.jpgPhoto on 3-22-23 at 2.04 PM.jpgPhoto on 3-22-23 at 2.05 PM.jpg

I have the 6GT barrel soaking/filled with penetrating oil and will check on it in a couple of days or so, but from what I've seen so far, it seems as though the penetrating oil softens up and/or lifts the carbon and then the Iosso wipes it out... I'm not exactly sure what the Eliminator does anymore besides wipe out shit that anything else would wipe out and make some patches blue for a little while lol.

I probably should have mentioned it earlier, because it could matter, IDK, but the only powder that was ever used with the 6CM barrel was Sta-Ball 6.5 which is pretty dirty stuff (and FWIW I'm exclusively running Shooter's World Precision Rifle in the 6GT which has run pretty clean so far).

(Now I've got to go load up some 6CM rounds so I can see if this fucker shoots again...)
 
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I've been using Kroil and Hoppes #9 just because I like the smell. LOL A little dab behind the ears and I'm ready for a night out.
 
I got a chance to measure the throat on the 6CM barrel that may or may not be back from the dead...

When new the distance to the lands was 2.245", after 2300rds... 2.280".

35 thou gone (doesn't seem like much, crazy).

Hopefully, I'll be able to get to the range tomorrow...
 
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It's alive.

~5-10mph winds and was hammering a 33% IPSC at 750 yards off of a tank-trap/Shmedium.

I shot a quick 5-shot group off the bench/bag/bipod without trying too hard while the wind was still gusting (top circle). I thought it sucked at first, but after closer inspection, it was just random mud from someone else's splash. Then, my last 2 rounds before I left to see if my zero was legit (middle and bottom). The circles are 1/4":

tempImage4WBZN8.png
tempImageXYVuKv.png
 
What's crazy is, I still have no real idea what exactly is happening here with this barrel?

The rounds I shot today were BTO 2.180", 100 thou off where the lands start now. Looks good, I'm not going to mess with it further.

A few months back I got into a back-and-forth in the 6CM thread with @reubenski surrounding the fact that the lands didn't seem to be eroding much if at all... and it turns out, he was right and I was wrong.

It was eroding more than it seemed (35 thou more). Most of the argument was surrounding whether or not I was measuring to the lands correctly or not, but it turns out I was measuring just fine, I was just measuring the baked-on hard carbon that was layered on top of the steel too. I cleaned the gun regularly and it continued to shoot and hold .5moa for a long time, but, I had no idea the Eliminator was leaving so much shit behind.

Which may or may not have been sort of protecting the barrel until the carbon buildup finally choked it out?

IDK? Would it have made it this far if I had cleaned it more aggressively for the first 2300rds, or not?

I've only got 500 more LRPs left on the shelf, and I half hope it doesn't make it that long, as then I'll have to either buy some SRP 6CM brass or score some LRPs to continue this "experiment"...
 
What's the load you're using?
Lapua ex-22-250Rem fire-formed into 6CM (after 14 firings they're still all ~1.900" and I've never trimmed them, they started short ~1.890")
CCI 200 LRP
41gn Sta-Ball 6.5
112gn Barnes Match Burner
CBTO 2.180"
Avg 2830fps - I put 5 shots over a buddy's Magnetospeed, hot barrel, rapid-fire style, and it was something like an SD 9 and ES 24.
 
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I also love kroil, but you guys be careful with this stuff. I think it could be what contributed to the tumor I am currently at MD Anderson Cancer center with. Definitely use gloves and dont be ignorant like me.
Why do you think Kroil might have contributed to a tumor?
We use it at work in volume.