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WTF barrel worms?
- Thread starter Sako man
- Start date
Not to open a can of worms here....pun intended...
But I just learned something in the last few weeks that it is possible that it is a build up and not pitting/etching.
It's a growth of some kind is a possibility.
Later, Frank
But I just learned something in the last few weeks that it is possible that it is a build up and not pitting/etching.
It's a growth of some kind is a possibility.
Later, Frank
Barrel Worms part Deaux.
I have come to a conclusions that you may want to hear about. In a previous thread, I was noticing some of my high value barrels degrading in accuracy quickly. I decided to scope them and found a common theme amongst the barrels that shot the worst. I had dreaded "barrel worms" or what is referred to as filiform corrosion, image below.
I have seen this issue in several of my barrels, and I now know what is causing this. It's the use of the cleaner called M-Pro 7, inside the bore. When there is carbon built up and NOT completely cleaned out, then covered with M-Pro 7, a chain reaction kicks off, moisture in the air probably contributes. After sitting for a few months filiform corrosion starts to weave it's way outward and under the coating of M-Pro 7.
Here is another barrel below that was only cleaned with M-Pro 7, and nothing else. As you can see the same pattern is starting, albeit not as bad as the totally ruined AI barrel above.
This is the stuff. I am sure people will balk, "it couldn't be that! it's supposed to clean and protect!" Well, it's probably in combination with a lot of things like how the guns are stored and moisture. But the agents in M-Pro 7 are the catalyst. My other barrels that are not cleaned with this stuff, or cleaned at all for that matter do not have the same issues. After months of trying to figure this out, this is my conclusion. As per Frank Green on the site I am now using Hops #9, and chasing it with a lite coat of CLP, hopefully it does the job of stopping any further corrosion. Heaven forbid I would ever destroy any of my Bartlein barrels, that would be a disaster.
I have come to a conclusions that you may want to hear about. In a previous thread, I was noticing some of my high value barrels degrading in accuracy quickly. I decided to scope them and found a common theme amongst the barrels that shot the worst. I had dreaded "barrel worms" or what is referred to as filiform corrosion, image below.
I have seen this issue in several of my barrels, and I now know what is causing this. It's the use of the cleaner called M-Pro 7, inside the bore. When there is carbon built up and NOT completely cleaned out, then covered with M-Pro 7, a chain reaction kicks off, moisture in the air probably contributes. After sitting for a few months filiform corrosion starts to weave it's way outward and under the coating of M-Pro 7.
Here is another barrel below that was only cleaned with M-Pro 7, and nothing else. As you can see the same pattern is starting, albeit not as bad as the totally ruined AI barrel above.
This is the stuff. I am sure people will balk, "it couldn't be that! it's supposed to clean and protect!" Well, it's probably in combination with a lot of things like how the guns are stored and moisture. But the agents in M-Pro 7 are the catalyst. My other barrels that are not cleaned with this stuff, or cleaned at all for that matter do not have the same issues. After months of trying to figure this out, this is my conclusion. As per Frank Green on the site I am now using Hops #9, and chasing it with a lite coat of CLP, hopefully it does the job of stopping any further corrosion. Heaven forbid I would ever destroy any of my Bartlein barrels, that would be a disaster.
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Thanks for the info^ Did you contact them ?
I’m sticking with wipe out and patch out even though it can take a few soakings.
I’m sticking with wipe out and patch out even though it can take a few soakings.
That m pro stuff seems to be hot garbage.
Buddy has been having pressure and accuracy issues, said he’s been cleaning the barrel regularly.
I asked him what he’s using and when he said m pro l laughed.
Bore scope showed a barrel that looked like a spiral Tony the Tiger.
All copper and carbon all the way to muzzle!
I’ve had excellent results with wipeout and am experimenting with the occasional iosso scrub when needed.
Buddy has been having pressure and accuracy issues, said he’s been cleaning the barrel regularly.
I asked him what he’s using and when he said m pro l laughed.
Bore scope showed a barrel that looked like a spiral Tony the Tiger.
All copper and carbon all the way to muzzle!
I’ve had excellent results with wipeout and am experimenting with the occasional iosso scrub when needed.
@Sako man
I think you are barking up the wrong tree. I have had “barrel worms” in a very old hunting gun and a recent barrel. Both are carbon steel, are yours carbon or SS? Anyway, my barrels have never seen M Pro, don’t own the stuff. My WAG (Wild A ss Guess) is it’s from moisture attracted to the powder and/or copper fouling left in the barrel.
I think you are barking up the wrong tree. I have had “barrel worms” in a very old hunting gun and a recent barrel. Both are carbon steel, are yours carbon or SS? Anyway, my barrels have never seen M Pro, don’t own the stuff. My WAG (Wild A ss Guess) is it’s from moisture attracted to the powder and/or copper fouling left in the barrel.
I am going to agree here.
There's less than 10 people (at most) that posted in here about both using mpro7 and seeing barrel worms, and all of a sudden someone has asserted an absolute based on the coincidence (not correlation) of the two.
There is no concrete proof of "I used it and then it happened", no timeline to verify how quickly it sets in (or how slowly), do you need repeat uses? does a singular use "taint" the barrel? Does it react to certain cleaning media or specific brush materials?
Lots of significant questions without answers.
Its too early (and very irresponsible) to be throwing out these kinds of statements, and Mpro7 is a popular product, so its likely going to be seen in higher use, regardless of peoples instance of barrel worms or not.
I shot an AR class that provided samples of it to everyone. I think its supported by some instructors because of its formula not using specific chemicals that may or may not be known carcinogens (I have no opinion on the validity or lack thereof regarding that statement)
You have to be even more careful with chrome moly steel barrels. They will pit/corrode even faster than the SS barrels.
Just from putting them (any of the barrels both ss and cm) away dirty and not cleaning them in a given time frame (varies by location and conditions) the barrels will corrode/pit. The fouling in the bore is reacting with the air conditions etc….
Put it away dirty and given x amount of time….I guarantee pitting will happen. It’s just a matter of time.
I did not, I guess that should be next on the list, I am wondering how they will react. I am soaking in Hops 9 for 20 min then whipping it out. Then storing in the safe with some dehumidifier containers. I have some Goldenrod dehumidifier's on the way as well. I'm pretty pissed as my second Tikka barrel is Fubar'd, it used to shoot 1/2 but today it shot about an inch or over.
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Read my comments please, I am not saying that M-Pro 7 caused the issue, I am saying that it contributed and acted as a catalyst under the conditions. I take responsibility for how I have stored my barrels. But....If the stuff worked as it's stated, meaning it has anti corrosive properties then why would I be getting these issues in the barrels I am using it in? It would stop the corrosion correct? But it's not stopping corrosion. Filiform corrosion happens when there is a layer covering the corrosion and it burroughs and creates the specific pattern. I have ruined enough barrels to come to this conclusion. I am not going to just throw this out there and try to ruin the reputation of a product, no point in that. I am basing my assertion on observation, not anyone else's anecdote.
Tell you what, go buy some, use it in your barrels. Let me know what happens. I'm betting you won't do that, because you won't risk loosing a barrel, that's because you know there is a possibility I am correct. You are only guessing that I am mistaken.
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I’ve got some sitting on my bench now. The bottle is almost empty. No issues yet.
I store all my guns/barrels with a light coat of Hoppes in them. I say it protects as good as any oil.
When I pull the gun out to shoot it....I run a fresh light wet patch down the bore and then dry patch the bore out. Hoppes will partially evaporate over time and get thick/gummy. Also it will keep cleaning although really slowly. So don't be surprised when you run a couple of patches down the bore if they come out a little dirty especially as the barrel gets more and more rounds on it. As the throat cracks and wears the solvent will lay in those cracks/fissures in the steel. The solvent will loosen it up over time. It's been called/referred to as "the barrel is sweating".
I am speculating about your situation somewhat, but I've seen this exact thing before. I was told by some very smart guys it's common in stainless alloys where the carbon content is relatively high (416 and other barrel stainless alloys fall into this category). I worked at a major aerospace manufacturer, and was told that it's where the iron isn't fully solulized during the alloying process, and crystalizes forming this pattern during solution hardening or tempering. The material engineers concluded that it was the result of "Inclusions". During machining, the part of the metal that had high carbon content (area of inclusion) begins to corrode as soon as it hits oxygenated air.
My job was to use acids (nitric, hydrochloric, sulfuric, and hydrofluoric) to clean and etch newly machined parts, to bring them to final tolerances; usually taking .0003-.001 off the surface in etching. (Carbon steel etches far quicker than the stainless alloy, so it creates the channels just like you're looking at). After a water bath, and an hour in a 170* dryer, they'd come out of the baskets looking just like this.
The company tracked it down to poor material control, and switched vendors. Never came back.
I'm certain what you're seeing is evidence of these metallic inclusions in the bar stock the barrel maker couldn't have known was there, unless they acid etched every barrel after the rifling process, and bore scoped each one just to check for this. I believe what you're seeing now is the result of the natural galvanic corrosion of the dissimiliar metals over time. Firing the first few rounds would cook out the corroded metal, leaving the corrosion etchings void of surface metal.
Having just come out of the etching, 100% virgin metal would look like this an hour later. I wouldn't beat yourself up too much about your storage practices, unless you see other forms of corrosion besides the inclusions I'm seeing here.
The thought of worms is humorous to me. I thought it looked like a fungus or ivy root system, as if it had somehow grown into the metal.
My job was to use acids (nitric, hydrochloric, sulfuric, and hydrofluoric) to clean and etch newly machined parts, to bring them to final tolerances; usually taking .0003-.001 off the surface in etching. (Carbon steel etches far quicker than the stainless alloy, so it creates the channels just like you're looking at). After a water bath, and an hour in a 170* dryer, they'd come out of the baskets looking just like this.
The company tracked it down to poor material control, and switched vendors. Never came back.
I'm certain what you're seeing is evidence of these metallic inclusions in the bar stock the barrel maker couldn't have known was there, unless they acid etched every barrel after the rifling process, and bore scoped each one just to check for this. I believe what you're seeing now is the result of the natural galvanic corrosion of the dissimiliar metals over time. Firing the first few rounds would cook out the corroded metal, leaving the corrosion etchings void of surface metal.
Having just come out of the etching, 100% virgin metal would look like this an hour later. I wouldn't beat yourself up too much about your storage practices, unless you see other forms of corrosion besides the inclusions I'm seeing here.
The thought of worms is humorous to me. I thought it looked like a fungus or ivy root system, as if it had somehow grown into the metal.
@Frank Green have you ever seen this happen with any Bartlein barrels? I know you try to control the alloys pretty well and work with the mill closely.
Just trying to see if we can expand on what @Kanwhitetails just said.
Also if people don't know Frank Green is Bartlein.
Just trying to see if we can expand on what @Kanwhitetails just said.
Also if people don't know Frank Green is Bartlein.
Is it just me or does anyone else hallucinate after using Hops #9?
I need to try this wipe out stuff perhaps!
I need to try this wipe out stuff perhaps!
I have two gallons from Grandpa. It's my favorite smell, closely related to the premium gasoline odor from the mid 80s. Well, this and Jet A... call me crazy.
Not sure exactly what you are asking in the terms of have I seen it happen? You mean during the barrel making process? I'll say no. Not what is in the pictures at the beginning of this thread.
Have I've seen barrels guys have sent in and or brought back after shooting with these barrel worms/pitting/etching in them? Yes. I'll say though it isn't common. Maybe like two a year or so and at times if that.
Hard to say if it's in the steel from when it was made. It's rare and I mean rare we ever find a piece of steel with voids in it from inclusions in the steel. If I had to put a number on it...like maybe 6 barrels in 20 years out of tens of thousands that we've made.
I do feel it's more from cleaning or a lack of cleaning and putting the gun away dirty etc...it's a chemical type reaction.
Just recently I sent a barrel out to the lab. Barrel had like 80 rounds on it. It had what looked like a few random pits in it (not the barrel worm syndrome). When I got the lab report back and the pictures which we're magnified inspected at 200x, 300x and 500x magnification. This is what they found...this is the short version....
The point indications were corrosion tubercles on top of shallow pitting corrosion sites. 2. The tubercles contained sulfur and chlorine as notable elements. The chlorine suggests use of an improper cleaning substance or otherwise unfavorable environment. 3. No indications of voids or porosity within the metal were observed. 4. No issues with the raw material were observed.
So in the first sentence look what it says... (on top of shallow pitting) but they stood proud about +.004" up from the surface. They where not what I though where pits or voids. So where did the chlorine come from?
Later, Frank
Frank, thanks for the insight, once again, your commitment to this community is truly impossible to put a value on.
Do think you fouling shots will "fill in" those types of pits, or is it something thats a one way street in terms of barrel degradation, if it sets in?
I also emailed your team about the cleaning procedure you mentioned, thanks again, I got a human written response pretty immediately too, which kinda shocked me. Cant wait to order one of your barrels for my next build based on this level of service.
They pass it out because its free or they are paid to. Most of these clowns don't know shit about real weapons maintenance.
Worrying about carcinogens when you are covered in copper , lead and carbon dust is LOL.
Tubercles. I learned another new word today. Thanks Frank.
I'll add this from memory sparked after the fact. The roots didn't show up until the parts had been hardened. Their initial tests were to cut up blocks of raw material and run them through the chemical process line and see what was found. Nothing, they were perfect. Then someone mentioned that when we saw the issue was after some steps were alread completed in the process, including post-machining annealing and subsequent solution hardening. So, a new block was cut up, the pieces hardened, and the chem process was completed. Low and behold, the root like corrosion appeared. This was when the determination was made that it was the softer metals precipitating out during hardening.
The material defect was an expensive discovery. I can't imagine how damaging this could be to a customer of a metal supplier. In this case, they had to find a way to test every part from that lot of material, which needless to say included removing bulkheads and structural pieces from several aircraft already in final assembly. That was a mess. Thankfully we found the issue quickly into using that batch.
Bartlein makes phenominal barrels. Some competitive folks I know spin several to use themselves each year and won't buy anyone else's tubes. Good enough for me.
I'll add this from memory sparked after the fact. The roots didn't show up until the parts had been hardened. Their initial tests were to cut up blocks of raw material and run them through the chemical process line and see what was found. Nothing, they were perfect. Then someone mentioned that when we saw the issue was after some steps were alread completed in the process, including post-machining annealing and subsequent solution hardening. So, a new block was cut up, the pieces hardened, and the chem process was completed. Low and behold, the root like corrosion appeared. This was when the determination was made that it was the softer metals precipitating out during hardening.
The material defect was an expensive discovery. I can't imagine how damaging this could be to a customer of a metal supplier. In this case, they had to find a way to test every part from that lot of material, which needless to say included removing bulkheads and structural pieces from several aircraft already in final assembly. That was a mess. Thankfully we found the issue quickly into using that batch.
Bartlein makes phenominal barrels. Some competitive folks I know spin several to use themselves each year and won't buy anyone else's tubes. Good enough for me.
Cleaning products for guns (like gun lubes) are at a weird point in the market, where marketing has entirely surpassed data, as a reliable source.
Cars have this problem too. Everybody has a sweet heart brand for motoroil, or cleaning products, then the blackstone labs guy goes in an interview and says he buys whatever is on sale, when asked what his preferred brand is, and blows everyone's mind.
We're at a point where its likely that most of the products on the market perform equally, and more than enough to clean. I dont have enough of a scientific background to prove/disprove one over the other, or the desire (and time) to even attempt to do so. Everyone chooses to believe whatever they want to at this point, regardless of actual data (or lack thereof) to backup those beliefs.
I remember when the price went through the roof for AEROSHELL 64 just because Arfcom found out it was "milspec", and acted like it was jelly gold, ignoring the fact that there's stuff in tubs at the autoparts store, that EXCEEDS milspec requirements for lube, for a better price, and in higher quantity, that you can get NOW, instead of mail ordering from some guy who's making a killing splitting a tube of aeroshell into 20 makeup sample glass containers
I don't disagree, imperical experiment should be explored.
Most believe because what the marketing team says on the packaging. I did this to my detriment, and over $1500 bucks in barrels.
Then there are some who will hear from word of mouth, anecdotal evidence for products that have been around for years, such as Hops #9, or Wipeout.
Proper ventilation aside, I took an entire evening going through every barrel I have with Frank's protocol. With the addition of good humidification I suspect I should be good from here on.
Expensive lessons...
You're essentially still making the same mistake that you're discussing now.
1. there's still no proof mpro7 did whatever you're saying it did to your barrel. correlation isnt causation.
2. Hoppes #9 isnt anywhere near the same formula it was originally, so saying that its "been around for years" is irrelevant.
Your welcome!
As my gut would say..."no I don't think fouling shots will "fill" it in per say and help you accuracy wise. It possible but I'll say odds are against it.
It also can depend on where these barrel worms are at. If towards the breech end I'll say it won't effect you as much but if it's towards the muzzle end/crown end of the barrel...then I think the problem will be worse.
Also if it's causing copper fouling issues....then for sure it's going to effect accuracy.
If it's your gun do this...shoot 25 rounds thru the barrel from clean. If the accuracy starts going sour in about 12-15 rounds...you've got problems.
Best I can tell you bud!
You're arguing just for the sake of arguing. Let us know how that works out for you in life.
Your welcome on the new vocabulary word!
Thanks for the compliment also!
Interesting read on the heat treatment and the chem process above.
Not really. Im asking you to stop misrepresenting a product causing this issue, until you have actual data that proves it.
If you truly believe MPro7 caused this issue, why are you not holding them responsible for it?
Also, if that was true, why wouldnt we be seeing more instances of this mentioned, outside of this thread? the product isn't only sold to snipershide members.
Do yourself the favor and go back and read my statements, perhaps you did not, or you are not processing things. I am not holding them solely responsible, because though I had used their product as directed, I provided for a sub optimal storage environment. Though they have an ineffective product, I have accountability.
The fact of the matter is that until recently few had the access to cheap bore cameras, I suspect there will be more on this subject from others in the future.
Because maybe he has integrity and will take responsibility for something he thinks he did.
Never used MPro7 cleaner but I do run a light patch of the MPro7 oil down my barrels for storing. This has me worried. About to go dry patch them all out and coat with CLP 
With all things cleaning + barrels: After a while reading upon the topic I have an irresistible urge to throw in the towel and just store my rifles in a vat of Mobil 1.
Maybe after a good internal pressure washing (with oil) lol.
Maybe after a good internal pressure washing (with oil) lol.
Transmission fluid!
Knew a old collector machinegunner. After he ran his guns hard…he came home and had a 55 gallon drum of transmission fluid. As long as the gun didn’t have like a wood stock on it…and after some cleaning…he’d dunk the whole gun into the 55 gallon drum.
I never tried it and off hand don’t know if I’d recommend it but can’t hurt. Trans fluid is great stuff!
Look up Ed’s Red bore cleaner formula. I’ve never tried it but it does have tranny fluid in it as well.
See? I knew I was a genius.
I'll set up three 55 gallon drums in the living room; one filled with Mobil 1, and the other filled with trannies, uh, I mean transmission fluid, and finally, one with Patch-Out. I'll first dunk the guns, scope and all, into the Patch-Out and leave them for 3 days. Guns with wood will then be stored in Mobil 1, and the non-wood guns will rest with the trannies-mission fluid.
If the wife complains, I'll toss her into one of the drums.
Done. Endorsed by Mr. Green.
I'm gonna be a fricking millionaire! somehow
Im not sure what you consider “recently” but cheap bore scopes have been quite common for the last few years. 16,000+ reviews just for one on Amazon.
If a product as common as mpro7 was causing barrels to erode like this, it would be a more commonly known issue.
People routinely complain about much lesser things.
We’d be hearing about it regularly, like how commonly Fram filters collapse.
I use MPro7/Hoppe’s Elite. I’ve been using it for years. No barrel worms here
I’ve had barrel worms in the past, one or two of my 260 barrels, can’t say I noticed any I’ll effects.
Guess I was lucky.
Back then I was running quite extended times without cleaning.
Advice then was similar to now, avoid really dirty barrels and use proper cleaning methods.
I’ve recently bore scoped all my barrels but one(
my 260) and all look good.
I’ll give the 260 a good clean tonight and take a look.
I’m probably taking it out to play this weekend anyways.
Kinda miss the little gal.
Guess I was lucky.
Back then I was running quite extended times without cleaning.
Advice then was similar to now, avoid really dirty barrels and use proper cleaning methods.
I’ve recently bore scoped all my barrels but one(
my 260) and all look good. I’ll give the 260 a good clean tonight and take a look.
I’m probably taking it out to play this weekend anyways.
Kinda miss the little gal.
You need ivermectin just like Rogan did, that’s what the internet said.
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I do not doubt that's the case for most people. I believe I met several conditions that lead to corrosion, possibly a trifecta, one of those being environment/humidity. Possibly being close to a coastal region contributed.
I did speak with a cousin in Alaska yesterday who owns a ton of firearms, and he avoided M-Pro7 as he felt it was too mild and didn't clean as effectively as other products, and left some residue and carbon behind in places. It is mild in nature. Apparently his go to is OTIS foaming bore cleaner, Hops#9, sometimes even ultrasonic cleaner followed by air compressor. Every season he runs a few patches of JB paste through his high value guns. All this followed up by CLP or Hops oil. Heavy duty to say the least.
I think MPro may be fine for the outside of a firearm, and possibly trigger and bolt areas, but the bore is another story and requires special care.
I have since installed dehumidifier rods in my safes. I am guessing this should help. Those of you who live in warmer regions like Arizona may not need this, however more humid or coastal regions could benefit by investment in de-humidification.
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Ivermectin... lol
If the apple flavor doesn't work, the black licorice certainly will...
If the apple flavor doesn't work, the black licorice certainly will...
Reviving this thread...
I have recently been diagnosed with the dreaded "barrel worms".
This is my 22-250 barrel. I don't scope it every time I clean it, but I keep track of every round fired by date, and every cleaning.
It happened somewhere between 218 (2/13/22) and 742 (11/14/24) rounds. Looking at my notes, it's not uncommon for it to sit dirty for several months during this time span.
What's odd is that I scoped the rest of my 10 rifle barrels, and this is the only barrel with this issue. I even have another barrel from the exact same manufacturer that uses the same powder, and I've used a similar cleaning regimen on, and it does not have this issue.
Notes:
- All of this occurs in a section of the barrel about 3" to 6" from the muzzle. There is a lot of it in that stretch, but nowhere else.
- All rifles are stored in the same safe, inside my house, in the upper-midwest, with two of those rechargeable silica dehumidifiers.
- All barrels are stainless.
- All are cleaned primarily with Boretech Eliminator. -- I've never owned that M7 or whatever stuff referred to earlier in this thread.
- All rifles are shot suppressed.
- This barrel still shoots pretty well. I'd have to shoot it a bunch more to see if and by how much precision has decreased.
Now, I'll admit that my dehumidifying solution for the safe could be better. I don't stay on top of those rechargeable packs as well as I should. Maybe a plug-in style rod would be better. And obviously, I should clean them if I'm going to let them sit for a while, but I don't always know when that will be.
Any new thoughts from the crowd? Could I be lucky enough to summon @Frank Green ?
Considering the location of the "worms" is limited and none of my other barrels have this issue, I'm inclined to think that a defect in the steel could be a factor. However, this was not seen the 2 other times I scoped this barrel, at 0 and 218 rounds.
I have recently been diagnosed with the dreaded "barrel worms".
This is my 22-250 barrel. I don't scope it every time I clean it, but I keep track of every round fired by date, and every cleaning.
It happened somewhere between 218 (2/13/22) and 742 (11/14/24) rounds. Looking at my notes, it's not uncommon for it to sit dirty for several months during this time span.
What's odd is that I scoped the rest of my 10 rifle barrels, and this is the only barrel with this issue. I even have another barrel from the exact same manufacturer that uses the same powder, and I've used a similar cleaning regimen on, and it does not have this issue.
Notes:
- All of this occurs in a section of the barrel about 3" to 6" from the muzzle. There is a lot of it in that stretch, but nowhere else.
- All rifles are stored in the same safe, inside my house, in the upper-midwest, with two of those rechargeable silica dehumidifiers.
- All barrels are stainless.
- All are cleaned primarily with Boretech Eliminator. -- I've never owned that M7 or whatever stuff referred to earlier in this thread.
- All rifles are shot suppressed.
- This barrel still shoots pretty well. I'd have to shoot it a bunch more to see if and by how much precision has decreased.
Now, I'll admit that my dehumidifying solution for the safe could be better. I don't stay on top of those rechargeable packs as well as I should. Maybe a plug-in style rod would be better. And obviously, I should clean them if I'm going to let them sit for a while, but I don't always know when that will be.
Any new thoughts from the crowd? Could I be lucky enough to summon @Frank Green ?
Considering the location of the "worms" is limited and none of my other barrels have this issue, I'm inclined to think that a defect in the steel could be a factor. However, this was not seen the 2 other times I scoped this barrel, at 0 and 218 rounds.
