how to rust free bore?

[nekshot]

I am ready to build another ml and I got the barrel out of storage (from a pawn shop salvaged gun) and the bore is lightly rusting. This is after a very careful clean up 12 month ago. I want to get this bore clean to metal so I can treat it with this SENTRY bore conditioner. My question is would naval jelly be ok in the bore? Or any other ideas, I used Kroil on it 12 month ago.

[johnson1942]

mix some anti freeze with a bore cleaner and try that. antifreeze has every thing that fights rust in it. it may also take it out well with out hurting the bore. it mixed with water is good to swab a bore between shots also.

[oldred]

First wash out the bore with a good solvent to remove any traces of oil then swab the bore with a Phosphoric acid solution, easy to find at almost any auto body paint supply store, Lowes, Home Depot, etc (Ospho is the oldest brand, it's been around almost 100 years). The Phosphoric acid will dissolve any rust it comes into contact with and leave a thin Phosphate coating that will neutralize any traces of rust remaining, Phosphoric acid "puts out the fire" and actually STOPS rust while oils and the rust inhibitors in antifreeze, no matter what the combination, will only smother rust and hold it at bay until it is removed (such as after the first shot in a gun barrel). Phosphoric acid will attack the rust and stop new rust from forming but it will not harm the base metal, put out the fire first THEN use oils and other inhibitors to keep new rust from forming.

[Garyshome]

Good post...thanks

[mazo kid]

I would NOT use Naval Jelly on any of my bores! Light flash rust will clean up with 0000 steel wool, followed by a couple of clean patches and then use any good gun oil to oil that shiny bore.

[William Yanda]

What is the active ingredient in Naval Jelly? I was under the impression that it was an acid, perhaps phosphoric, thickened to assist in its use as a stripper. Respectfully, Bill

[lancem]

What is the active ingredient in Naval Jelly? I was under the impression that it was an acid, perhaps phosphoric, thickened to assist in its use as a stripper. Respectfully, Bill
I believe you are correct.

[nekshot]

seeing as last year I really put elbow grease into cleaning this barrel I did the unthinkable and swapped it with navel jelly. Washed it out and warmed it up to make sure it was dry and gave it the bore conditioner and boy did this bore get slick! Can't wait to get this build done so I can shoot it and see how the bore reacts to this Sentry product with black powder. I made a decision a couple years ago to stay with real black because of residue left behind and ruining a good piece of gun.

[fouronesix]

Naval Jelly is basically phosphoric acid. It will dissolve rust and blueing and any number of other things. It will lightly etch steel surfaces and should be completely removed to prevent potential for rusting. Kroil is not the best rust preventative but is a fairly good penetrating oil. Many times bores put in storage that haven't been cleaned correctly or treated correctly will show rust. "Flash rust" is an often used or parroted term for those who don't like to use hot soapy and hot rinse water for cleaning muzzleloader bores.

[flydoc]

evapo-rust (available in most auto stores) will destroy the rust and not attack the base metal, like acids can. Been using it for years. Plug the nipple hole and pour it in , let it sit a half hour and then pour it out. Viola! If you let the residue dry naturally it will prevent flash rusting for another two weeks or so. Its about $25 a gallon, which goes a long,long way. The liquid you pour out is often still capable of working for a long time, just keep it separate from the unused stuff and reuse it until it quits working.I usually pour the used stuff through a cloth or paper filter to remove rust particles and sludge.

[oldred]

Naval Jelly is basically phosphoric acid. It will dissolve rust and blueing and any number of other things. It will lightly etch steel surfaces and should be completely removed to prevent potential for rusting.


Phosphoric acid is not at all like Hydrochloric (muriatic) or Sulfuric acids and it does NOT need to be completely removed or neutralized, simply rinse with water and wipe it dry but if you remove it completely you will remove the protective phosphate coating. Phosphoric acid protects the metal from rusting it will NOT cause rusting, just the opposite in fact and it has been used commercially for this purpose for over a hundred years. Don't confuse Phosphoric acid with strong acids just because it has "acid" in the name, Phosphoric acid is the same as what's in a carbonated cola such as Coke or Pepsi and no, in spite of the age old "urban legend" a nail will not dissolve in a bottle of coke!

Phosphoric acid will not corrode bare metal, it will leave a heavy grey coating if a heavy layer of it is left to dry but simply swabbing the bore with Phosphoric acid then rinsing/wiping dry will not only dissolve rust it will render any left inactive and leave a very rust resistant Phosphate coating.

[OverMax]

All these chemicals commented I know little about. And Naval Jelly's use which I do know about from prior use. One product I surely wouldn't try. (naval jelly) Frankly: I would simply used a brand name bore cleaner like Hoppe's #9 gun bore cleaner and a piece of Chore Boy copper scrubber for the purpose. Can't hurt nothing and if anything gained both would surely help with rust removal.

[oldred]

Navel Jelly is no good simply because it's too messy and has a lot of unwanted ingredients in it to make it cling to vertical surfaces, this will often leave a gummy residue if not thoroughly cleaned before it's allowed to dry. "Ospho", or another similar product, is water thin and works great. It's easy to apply with a thoroughly dampened bore swab, give it a couple of minutes to work then swab it lightly with a water dampened swab and wipe it dry. Any traces of oxidation will be neutralized and a very thin very rust resistant coating will be left. If for some reason the thoughts of a Phosphate coating bothers someone (Don't know why it should?) then simply rinse all the Phosphoric acid out with a wet patch before it dries but either way just oil down the bore after application and rusting will not happen.

Fellows Phosphoric acid has been used for YEARS as a rust preventive treatment for steel and iron, it's properties are well known and it's in no way the corrosive substance as what most folks think of when they think "Acid"! Phosphoric acid is the main ingredient in rust converters such as Permatex "Extend" metal treatment, it has been used for YEARS to treat rusty metal before painting to stop further rust after painting, this stuff INACTIVATES rust unlike oils or other sealers that simply smother rust and prevent contact with Oxygen, remove that oil and the rust starts to grow again! Rusting is Oxidation, the iron is chemically combining with Oxygen and the reaction will not stop simply by oiling which serves only to block the Oxygen, the Phosphoric Acid will actually stop the reaction rather than just smothering it, basically it "puts out the fire" and oils simply can not do this.

[fouronesix]

Phosphoric acid is not at all like Hydrochloric (muriatic) or Sulfuric acids and it does NOT need to be completely removed or neutralized, simply rinse with water and wipe it dry but if you remove it completely you will remove the protective phosphate coating. Phosphoric acid protects the metal from rusting it will NOT cause rusting, just the opposite in fact and it has been used commercially for this purpose for over a hundred years. Don't confuse Phosphoric acid with strong acids just because it has "acid" in the name, Phosphoric acid is the same as what's in a carbonated cola such as Coke or Pepsi and no, in spite of the age old "urban legend" a nail will not dissolve in a bottle of coke!

Phosphoric acid will not corrode bare metal, it will leave a heavy grey coating if a heavy layer of it is left to dry but simply swabbing the bore with Phosphoric acid then rinsing/wiping dry will not only dissolve rust it will render any left inactive and leave a very rust resistant Phosphate coating.

I know the difference and the chemistry involved. What anyone wants to do with their bores, go ahead and start treating with phosphoric acid. Make no difference to me. If a bore's surface is already rusted, corroded or etched from rusting then it makes little difference.

Phosphoric acid is used as a steel/iron sometimes galvanized (zinc coated) etching treatment prior to painting or for other coatings. I also know what etching is. It's also sometimes used as a flux. Since it's reactant by-products have a rust inhibitive effect (after the etching has occurred) for steel/iron (think sheet metal, structural metal, etc.) does not mean I'm going to use it for that in a bore! Oh, and don't get it on bluing and some other finishes :)

[oldred]

I suggest anyone wanting to try this to just use a piece of polished steel and do a little testing, you will easily see how much "etching" occurs! This subject was about treating a lightly rusting bore and Phosphoric acid is an excellent solution for that, swabbing it down with a Phosphoric acid dampened swab is not going to cause etching! What it will do is dissolve loose oxidation and render inactive any tiny traces of rust that might remain anywhere in the bore. I have used Ospho for this purpose since 1977 and I have treated a lot of rifle bores with it, everything from just light rusting to gross neglect and I can assure you that "Etching" is a non-problem! I suppose if a new bore were to be soaked in the solution for a significant amount of time some etching would occur but even with gross abuse such as that no significant damage would occur, not something that should be done but it wouldn't be disastrous if it did happen.

I use Phosphoric acid for many other things also and while it will instantly start to dissolve rust it does so without attacking the underlying metal, light rusting can be easily removed from a rifle bore and the bore left with no damage at all except from the rusting itself!

[Bullshop Junior]

evapo-rust (available in most auto stores) will destroy the rust and not attack the base metal, like acids can. Been using it for years. Plug the nipple hole and pour it in , let it sit a half hour and then pour it out. Viola! If you let the residue dry naturally it will prevent flash rusting for another two weeks or so. Its about $25 a gallon, which goes a long,long way. The liquid you pour out is often still capable of working for a long time, just keep it separate from the unused stuff and reuse it until it quits working.I usually pour the used stuff through a cloth or paper filter to remove rust particles and sludge.

This is what I was going to suggest, but be careful, it WILL remove blueing as well.

[oldred]

Anything that will chemically remove rust will instantly remove bluing! Done properly this need not be a problem however, swabbing a bore is done with a dampened swab not a saturated one that could spill out onto the finish.


If anyone wants to know before trying any of these solutions on a bore then a simple test can easily be done, I use Phosphoric acid because it works almost instantly where as chelation products such as Evap-O-Rust take a long time to work and are not particularly suited to simply wiping on then rinsing off nor do they work well unless the rust is saturated rather heavily with the solution.

Take a scrap piece of steel and polish it with successive grits of sandpaper down to about 400 grit, finer is better. Wipe the bare surface with water and set aside to allow it to lightly rust, wipe one side with a Phosphoric acid DAMPENED, not soaking wet, patch and see what happens to the rust. Immediately wipe this dry just as you would a rifle bore but then leave it as-is with the resultant Phosphate coating intact and no oiling. Clean the remaining side with oil, solvents, or whatever your favorite bore cleaner then wipe dry just as you did the other side, give this a bit of time in a humid environment and see what happens to each side!

Another really good test is to let a piece of metal rust enough to produce light pitting then remove the rust on part of it with the Phosphoric acid solution and wire brush the rust off of the rest of the piece, give it a few days and compare the surfaces, check the difference between the Phosphoric acid treated side as opposed to the wire brushed part! Also this can easily show that the Phosphoric acid swab wiped over the cleaned metal will not even "etch" out the 400 grit sand-scratches. We did all of these things years ago when experimenting with different products when dealing with auto body rust, I have used these solutions for many years since then on everything from barrel bores to removing/treating rust for auto body repair to machinery rebuilding and I can assure you that etching of the bore is a non-issue.

[Fly]

I like the evapo-rust deal.I read up on that & heck it would last a long time if re used.

Thanks for the tip Flydoc, I also like your name (wink)

Fly

[Char-Gar]

Clean the bore with 0000 steel wool on a bronze bore brush and
kroil. Dry with clean patches and fire the rifle about five rounds and you are good to go. Keep chemicals far away from the rifle.

[oldred]

Keep chemicals far away from the rifle


Wow, Phosphoric acid is not some toxic corrosive chemical! It's main use is as a food additive, mostly used in soft drinks and in fact it's an old time hot-rodder trick to use Coke to remove rust from chrome car bumpers, but it's also widely used as a rust INHIBITOR yet it's being discussed here as if it will actually cause rust if it's not "completely removed"! Just because it has the word "Acid" in it does not make it a dangerous corrosive chemical, it can be handled with bare hands (although it will sting if you get it in a cut but then so does alcohol), it will not "eat" holes in your clothing and in fact I often use cotton balls to apply it, I have even had some splattered in my eye without harm other than severe stinging (again alcohol would be just as bad). Vinegar is also acidic and Citric acid will also remove rust and bluing but both of those could also cause more rust to form because of the different chemical composition so it's far more than just an acid issue.

This is a very benign substance I have been talking about and it works like a charm for removing rust from a bore or any other steel/iron surface without doing damage to that surface and it INHIBITS new rust from forming, all this scare talk about it is just that! As far as "etching" or destroying the metal surface it will remove rust even at the concentrations found in soft drinks, as per the old time hot-rodder trick, yet it doesn't seem to do much damage to Aluminum cans nor did it harm the old steel cans that soft drinks once came in! Yes in high concentrations and complete saturation it can be used to lightly "etch" steel surfaces, but then so can Citric acid, but it is chosen for this purpose specifically because of it's very MILD effects on the the surface, unlike some acidic chemicals that are sometimes used that would heavily etch metal surfaces. Besides that kind of application at concentrations such as that is not what we have been discussing anyway, the way it's used on a rifle and at the concentrations contained in rust removal products that's not what would be done to a rifle bore when swabbing out rust!

Check out line 6 in this list of uses in the link below

http://blog.fooducate.com/2009/06/30/11-quick-facts-about-phosphoric-acid-yes-that-chemical-in-coca-cola/

[oldred]

DiHydrogen Monoxide, also known as Hydroxyl acid, is another very "corrosive" chemical that will destroy the surface of the bore if you're not very careful with it, ,

DiHydrogen Monoxide (Hydroxyl acid) is a very dangerous chemical that will destroy a rifle bore unless used with the utmost care! Not only that but the stuff can easily kill you, in fact hundreds of people die from exposure to it every year in this country alone! Death can occur from inhaling even a small amount of this substance in it's liquid form and severe skin damage can occur from prolonged expose to it, it causes severe corrosion and oxidation of metals and in it's gaseous form it can cause severe burns to unprotected skin. It can in fact do FAR more harm to your rifle bore than that other nasty chemical Phosphoric acid and in fact one of the primary uses of Phosphoric acid is to counteract the damage to metal done by exposure to DiHydrogen Monoxide.

More info here,

http://www.dhmo.org/facts.html


Just a little humor there to try and put things in perspective, chemical names often scare people when they shouldn't! :p

[Char-Gar]

I never did understand that Gilberts Chemistry Set, I got for Christmas in 1950. But I do know how to get rust out of barrels without chemicals.

[oldred]

I never did understand that Gilberts Chemistry Set, I got for Christmas in 1950. But I do know how to get rust out of barrels without chemicals.

Nope you know how to get rust you can SEE out of barrels!

What you see, and what we normally refer to as rust, is actually just the oxidized residue left over from the oxidation (rusting) process! That residue is not the problem and simply removing it by brushing it off does little to stop the underlying problem where the reaction of iron molecules and oxygen is taking place, this must be removed or chemically treated to stop the rusting process, removing the ash does not put out the fire! This oxidizing layer can be sanded off or taken off with a grinder, neither of which are options inside a gun barrel so that leaves only trying to seal off the oxygen and temporarily smothering the process with oils or chemically treating it to more permanently stop the process. This is where products like a chelating agent such as "Evapo-Rust" or the Phosphoric acid come into play, they not only remove the already oxidized iron but stop the oxidation process from continuing which is ultimately what needs to be done. If you use any mechanical means of removing enough material to eliminate the actively oxidizing layer from the metal surface you will remove more metal and do more damage to the surface than any so called "etching" done by Phosphoric acid! Removing the red rust RESIDUE, the already oxidized and destroyed metal, is not nearly as important as preventing more damage from occurring by leaving the active surface and allowing it to continue converting the iron in your barrel into iron oxide! Removing the rust residue by brushing it out is one thing but stopping the actual rusting process is something altogether different, it's easy to remove the ash but much harder to put out the fire!


Just something you might want to consider, whenever you fire something like Pyrodex you will coat the barrel with far more damaging "chemicals" than that nasty ol' Phosphoric acid! The process of using the Phosphoric acid based rust preparations to remove and stop rust in a barrel bore is so benign it's really comical to even compare it to what's happening whenever the rifle is fired, especially when using one of the BP subs, you need to consider why the bore has rust in the first place rather than be afraid of something that will stop the problem from getting worse.

Of course this all assumes there is rust present for some reason and if there is no rust in the bore then no rust removing solutions need to be used anyway, once rust starts however and the oxidation process has begun you really need to put out the fire rather than just wire brushing out the ashes of your rifle bore!

[Char-Gar]

Give it up oldred! All that tech talk is wasted on me. I don't speak in tongues either. :-)

[oldred]

Give it up oldred! All that tech talk is wasted on me. I don't speak in tongues either. :-)

How about putting it like this then, rusting is oxidation where the iron molecules are combining with oxygen the same chemical process as being on fire. If you burn a material, be it wood or iron, it will leave an ash as a residue or byproduct of this burning process so when you have rust occurring in your barrel it is oxidizing the solid metal into an ash -that ash is what we normally call rust. Simply scrubbing away this material does little to stop the process much the same as removing ash from burning wood does little to put out the fire, it helps some because the "ash" residue tends to absorb and hold moisture, so unless steps are taken to stop this process (literally put out the fire) then the process will continue. Unless you stop this process it will simply continue to convert the metal in your bore into "ash", iron oxide or rust or whatever you choose to call it, oiling the bore down will smother and stop the process but only so long as the oil film remains.

The funny thing here is that if you wipe down a bore with Phosphoric acid and another one with Hydroxyl Acid (DiHydrogen Monoxide) and leave them for a few hours the one with the Hydroxl acid will sustain far more corrosion damage so the Hydroxl acid is even more damaging than the Phosphoric acid yet some of the warnings from some folks make it sound as if just handling this nasty chemical could cause your kids to be born nekid!

Hydroxl acid or DiHydrogen Monoxide is also expressed as H2O which is of course more commonly known as water!

Either Evapo Rust or one of the Phosphoric acid solutions will not only remove rusting in a barrel but it will stop further rust from forming, brushing and oiling only does one of those things!

[dondiego]

I have "rusted/oxidized/set on fire" several of my barrels recently. My friends call it bluing and browning. I put out the fire with oil.

[Char-Gar]

Oldred...put it anyway you want. I have been shooting and cleaning rifle barrel for 60 plus years. I have never had a barrel rust on me, but I have cleaned a few that came my way with rust in them. I have made it this far without all this foo-fa-ra stuff and will make it on out.

[big bore 99]

I've used something called IOSSO bore cleaner on a couple barrels I bought used that had some rust. Use it on a tight patch and scrug it for awhile. It's a very fine abrasive ,maybe pumice? It wont take out much, but will sure enough shine the bore. I've also used some very fine valve grinding compound in the same way. Always work from the breech end and don't get any in your action or ejecters for obvious reasons. I clean it out with some Hoppes #9 and a few clean patches afterwards.

[oldred]

Oldred...put it anyway you want. I have been shooting and cleaning rifle barrel for 60 plus years. I have never had a barrel rust on me, but I have cleaned a few that came my way with rust in them. I have made it this far without all this foo-fa-ra stuff and will make it on out.

I didn't say a person MUST use a rust preparation, just that it's a darn good idea. As far as all this "foo-fa-ra stuff" as you call it the fact is it's nothing new and it has been around and used for this purpose for more than the sixty years you mention, just because you have never used it doesn't mean it doesn't work!




I have "rusted/oxidized/set on fire" several of my barrels recently. My friends call it bluing and browning. I put out the fire with oil

That's the very point I have been trying to make, oil does not "put out the fire" (nor will it neutralize the acids in rust blue for that matter). Oils only smother rust by keeping the oxygen away from it but the oil allows the rust to stay active, remove the oil and the rust can form again. It won't matter much one way or the other as long as that oil film is maintained but if the rust preparations are used then the surface is much less likely to form new rust if the oil film is removed, in a rifle bore that will happen every time it's shot. Just as rust bluing chemicals are supposed to be neutralized prior to oiling by rinsing in a base (usually baking soda) to inactivate the acids and stop their reaction with the metal, these rust preparations inactivate remaining oxidation so that it will not continue to react with the metal when no oil is present to prevent contact with oxygen.

I never said rust preparations were an absolute necessity but the OP was about dealing with light rust in a barrel, using one of these not only makes the job much easier it's also very good insurance that makes the bore far less likely to form new rust rather than be reliant on just that oil coating to prevent it from re-rusting.

[starmac]

I used evaporust on a tc scout, it does remove the rust and easily. Daniel mentioned it will take off the buueing, lol he has seen the one that I used it on. I screwed up stupidly and tied a bag around the breech plug end and poured it in the barrel, when I removed the bag the 1 1/2 inches of blueing that it came in contact was completely gone. It did a beautiful job of removing the blueing, and apparently treats the metal, because this completely white metal has never even tried to get any flash rust on it since. lol

[oldred]

Yep it will remove bluing instantly! That's one of the reasons I prefer Ospho, a dampened swab pushed down the barrel means no actual liquid to spill over onto the finish but Evapo-Rust does an excellent job too even if it might be a bit messier. The only barrel I ever used Evapo-Rust on was very heavily rusted, I personally would have junked the thing, but the fellow wanted me to try and clean it up and reblue it for him. Since it was to be refinished on the outside anyway I just poured the Evapo-rust into a PVC pipe that had been plugged on one end and dropped the barrel into it so it could soak for a few hours, I also had a fitting attached to the bottom so I could use an air hose to bubble up through the solution to agitate it. This set-up was not for gun barrels but rather another use that I normally do with hydraulic cylinders but it was perfect for the task at hand, after a few hours the barrel came out of that pipe clean as a whistle inside and out with no trace of oxidation except for the pits where the rust had been.

[starmac]

LOL After seeing how pretty it took the blueing off of my barrel, I'm thinking it would be the stuff to use if a guy was going to reblue one, but my blueing was nice and I HAD no plans of refinishing it. lol

[oldred]

LOL After seeing how pretty it took the blueing off of my barrel, I'm thinking it would be the stuff to use if a guy was going to reblue one, but my blueing was nice and I HAD no plans of refinishing it. lol


I have used both products, the Evap-O-Rust in that one instance, and used properly either will remove every trace of bluing and rust from the metal but the anti-rusting properties that are so desirable inside the barrel will prevent bluing (either rust type or hot bluing) from occurring unless the surface is sanded first so that will still need to be done.

[Fly]

I can tell you guys this.Since I bought this bore camera, it is amazing the specks of
rust that is in a bore you thought was clean.I,m just like most here when it comes to cleaning & oiling
my guns.I,m going to try this Evap-O-Rust & be very careful to not get any on the finish of the barrel.

Fly (GREAT THREAD)

[oldred]

Evapo-Rust works great but it does need to start out very wet and stay wet in order to do so and it takes a while, still it will work for you and work well, Phosphoric Acid OTOH works in only a minute or so and can be applied with a well dampened (wet but not dripping wet) swab so that it's much easier to use without a damaging the bluing. Just swab the barrel for very light rusting or use a wire brush if it's heavier but either way it only needs to be in contact with the surface for about a minute or so (don't allow it to dry, you will need to reapply it if you do) then thoroughly swab with a patch wet with soapy water, dry and oil and the rust is history! I have done a lot of barrels with this stuff and haven't damaged any bluing yet, all it takes is a little care. Those little specks are what I was talking about, it's nearly impossible to remove those tiny, and still very active, specks by brushing so they will tend to remain in even very small pits and if rust is present then unfortunately some pitting may be also. The Phosphoric acid will convert any remaining active rust into an inert form so that it is no longer a problem even if the oil film is lost, however unless the rusting is severe it won't leave any to convert even if there is pitting.

[dikman]

I've been following this with some interest. The idea behind Naval Jelly (phosphoric acid) is, as you point out, to convert the rust to ferric (iron) phosphate and so provide a suitable base for painting. In the case of a rifle barrel that has some rust (and presumably some pitting - and as Fly has pointed out, if you poke a bore-camera down a barrel you will be amazed at what you'll see) presumably the same principles apply as per Naval Jelly, i.e. you remove as much loose rust as possible, usually by mechanical means, and then coat the remaining rust with the Phosphoric Acid, let it do its chemical process and then wash it off with water to remove any traces of unconverted acid. At least, that is what all the Phosphoric Acid-based rust converters I've seen say. They also say NOT to apply it to bare metal.
Anyhow, fine so far, you end up with the remaining rust (at least, the rust that the acid can get to) converted to ferric phosphate. No problems if you're treating metal panels, but there is one minor issue with regard to barrel bores, i.e. the melting point of ferric phosphate is 284*F. I don't think that's going to last very long inside a barrel with black powder being detonated. It's also slightly soluble in cold water (I don't know if it dissolves quicker in hot water) so over time it would gradually be washed out by regular cleaning - if there's any left after firing the gun, that is. I have no idea if any of the stronger solvent cleaners/mineral distillates would also affect it.

[oldred]

then wash it off with water to remove any traces of unconverted acid.


At least, that is what all the Phosphoric Acid-based rust converters I've seen say.


They also say NOT to apply it to bare metal.



Not sure where you got your directions from but it appears you have two different products confused there, first off Phosphoric acid rust remover/metal treatment products (such as Ospho, Jasco, etc) and rust "converters" (Permatex Extend, etc) are two very different things! The rust converters contain Phosphoric acid (as do lots of products) but they also contain Tannic acid and other solids that are supposed to convert the rust and then leave a paint-like primer coating that is supposed to be painted over, obviously not something that would be used anywhere on a gun never mind inside the barrel! As far as the "wash it off with water to remove any traces of unconverted acid" I'm not sure where you heard that but the plain Phosphoric acid products are NOT supposed to be "completely" removed, although it is an option if you like, because doing so will remove the desirable Phosphate surface that inhibits further rusting. This is an extremely thin surface on a par with bluing and not a layer like paint (such as with the rust "converter" products) that simply needs to be wiped dry after allowing the Phosphoric acid to work for a minute or so, if heavily wetted and allowed to dry it still would do no harm but it would leave an undesirable powdery residue. Phosphoric acid does NOT need to be "neutralized" and indeed that thin dry coating is an excellent corrosion INHIBITOR (that's what the stuff is sold to do) not something that's going to cause rusting!


Also it's the synthetic latex rust CONVERTER products, (Permatex Extend, etc ) that are not supposed to be applied over bare unrusted metal, plain Phosphoric acid is often applied to bare unrusted metal to form the rust inhibiting barrier and in fact that's one of it's primary purposes.


The procedure for rust in a gun barrel is, for light rust a thoroughly dampened (not soaking wet) swab pushed several times through the bore for a minute or so and if this does not eliminate all the rust use a clean swab and repeat then wipe dry and oil. For excessively heavy rust a wetter application may be needed (in this case use care that it's not squeezed out onto the exterior bluing) along with vigorous brushing with a wire brush then THOROUGHLY wipe dry to prevent excessive build up then oil. If too much is left in the barrel to dry it will form a layer and some powdery residue that should be removed by re-wetting with the solution then wiping dry again, this layer/residue is not in itself harmful but simply is leftover unneeded gunk. Washing out the product completely is not needed nor desired since this will eliminate most of the residual rust inhibiting characteristics of the product and neutralizing is also unnecessary, we aren't talking about battery acid here!


Some of the confusion might be that while both products "convert" any remaining rust the products such as "Extend" are not just Phosphoric acid and contain more ingredients that are meant to be used as a primer under paint, auto body filler and other metal coatings. Plain Phosphoric acid is a rust remover that will "convert", or render inactive, remaining rust while conditioning the metal surface to chemically inhibit oxidation without producing a paint-like layer which is what the converter products do.

[dikman]

Thanks for the clarification about the commercial rust-converter products (not that I would put one of those down a barrel!). Still, if the end product of using phosphoric acid on rust is to create ferric phosphate then its relatively low melting point means it won't withstand the stresses inside a barrel when gunpowder is ignited.

Or have I got that wrong too?

[oldred]

Phosphoric acid products, including Navel Jelly, are meant primarily for dissolving and removing rust but it also converts any remaining iron oxides thus it's use in the converter products that are used to stop and seal rust but not remove it. Once the iron oxide is "converted" it's reaction with oxygen stops and it becomes inert so it will not continue to grow and this remains so even if the Phosphate surface of the surrounding metal is removed, this rust resistant (but not rust proof if exposed to excessive moisture) surface will disappear eventually but any remaining oxides in tiny pits will remain inert. This is why this stuff is so much better than just brushing and oiling a rusted bore, any remaining rust will be "dead" and will not become active again even if the treated surface is removed but it will remain active under oil and can (will!) resume the oxidation process as soon as the oil is burned off from firing. If the Phosphoric acid is washed away instead of just being wiped dry then while the old rust may be gone the bare metal will be immediately left reliant only on the fresh coat of oil for protection. As far as heat affecting the treated surface I use this stuff a lot on farm equipment, I am rebuilding an old John Deere hay wagon now, and I often weld parts that have had rust removed using Phosphoric acid (Ospho brand but there are others of the same product) about the only areas that seem affected are really close to the weld so it can take quite a bit of heat.


May be getting away from the main topic just a bit but there are lots of other uses for this stuff, it removes rust from tools and machinery and makes repainting rusty steel a lot easier. For instance on the hay wagon I mentioned, all that was necessary was to remove the old paint and any loose rust which I did with a small sandblaster (it could have been done by power brushing but the sandblaster was easier) then wipe it down with the Phosphoric acid using an old paint brush and let dry overnight. After it has dried any powdery residue is brushed away then prime and paint, as long as there was no loose or really thick rust remaining then that's all there is too it. As long as moisture can not reach the treated surface the rust will not come back under the paint, I have rusted items that have been treated/painted for over twenty years that still look good.

[6bg6ga]

It sounds like you have a chemical background. So if I may....what will take light surface rust off a blued barrel?

[oldred]

..what will take light surface rust off a blued barrel?

Nothing chemically without also removing the bluing, which itself is a form of oxidation. Your best bet for that is light oil and 0000 steel wool, rub vigorously and unless there are pits it should disappear almost completely. After rubbing with the steel wool you will need to make sure the surface is always protected by oil because it will tend to re-rust in those same spots if allowed to become dry of oil, unfortunately the chemical inactivation trick won't work here without severely damaging the finish.

Something else you might try if the rust will not satisfactorily erase with the steel wool is to use a coarser grade of steel wool and rub until the rust is gone even if it means wearing the bluing thin, at that point use Brownells Oxpho blue to restore the worn spot. I have done several this way and IMHO the Oxpho blue is about the best on the market for blending in a worn spot with the rest of the bluing.

[Idz]

This discussion reminds me of an interesting story I read years ago. The EPA was testing garbage dumps for illegal disposal of 'hazardous' waste by taking drill core samples. They found phosphoric acid and closed the dump, put on moonsuits, and excavated to track down the perpetrator. What they dug up were half empty Coke bottles from the local HS prom night.

[dikman]

The basic idea of using phosphoric acid, by itself, as a rust treatment is pretty neat, thanks for that, I've just never seen it mentioned anywhere else before. I use the stuff for Parkerizing, so it looks like I've just found another use for it :).

I'm still not convinced, however, that it will stand up to the explosive/corrosive environment in a gun barrel. For a display gun, no problems, but once it's actually used is another matter. Until someone can prove to me, beyond a shadow of a doubt, that it will successfully neutralize rust in a bore and keep it that way through repeated firing/cleaning cycles then I'll remain sceptical.

No offense intended, oldred, I guess it's just my nature to be sceptical about things when some doubt exists. Other than this, the thread has been most informative.

[oldred]

Well no the Phosphate surface of the bore will wear away but once the iron oxide is "converted" it is chemically changed so it is no longer actively trying to combine with oxygen, removing the chemical that caused the conversion does not make it revert back to iron oxide, or active rust.

Don't misunderstand, I'm not saying that you can treat a bore with Phosphoric acid and it will be rust proof for ever more nor will it negate the need for oiling. My point was that using the Phosphoric acid will leave a truly rust free bore (the original subject of this thread) whereas just brushing and oiling will leave traces of rust that are still actively trying to grow, when treated with these Phosphoric acid products the bore will not only return to it's rust free condition but actually be more rust resistant than when new until Phosphate surface wears away. Of course it's always best to not allow rust to form in the first place but unfortunately it happens sometimes and we have all, well most of us anyway, had to deal with it at one time or the other. It kind of boils down to this, the OP was about how to "rust free a bore" and brushing/oiling rarely can accomplish this completely while the Phosphate acid does so easily. While oiling can CONTROL rust it can not eliminate it and it will stay active but not grow until the oil is removed and it comes into contact with oxygen again, if however it is chemically eliminated by dissolving and/or undergoing conversion to a different and inert compound then the bore is no more likely to rust than a new barrel.

[Fly]

Well I went to Okla City this week end & got some grud getter rust removal & preventer.
It has Phosphoric acid in it.I will give it a try & report back.Since I have this bore camra
I can tell you guys for sure.

I will report back my finding. Fly

[oldred]

Grud getter or Krud Kutter? I have seen, but never tried, Krud Kutter but I am not familiar with Grud getter? It should be a watery liquid, probably either blue or green, and it should very lightly foam or bubble on contact with rust. But if it's a milky white thicker liquid then it would be one of the synthetic latex converter products and not what you want.

As has already been mentioned a few times, don't let any get on the bluing! This can happen by squeezing out of the swab entering the bore but more often by handling the barrel with some of the product on your fingers, just thought it worth mentioning again.

Just for grins&giggles if you have a piece of steel you could sand clean and let lightly rust, flash rust will form almost instantly on a wet sanded surface so just sand clean and then wipe with a wet rag. In a minute or so rust should have formed so at that point take a rag dampened with this stuff and just lightly wipe the rust and see what happens, you don't even have to wipe it just put some in a spray bottle and lightly spray the rust. Almost instantly and as if by magic the rust will simply disappear! Of course heavier rust takes a bit more time and effort but even more deeply ingrained rust such as a lightly rusted bore will still clean up in short order with a bit of swabbing. Using that trial piece before tackling your bore will give a much better idea of what needs to be done and how this stuff works, how much to use ,best way to to apply, etc. If you have something around with heavier rust you can soak it to either remove the rust or stop it, tools are a good example (this stuff is a real trick for rusty files!). Just be sure to thoroughly wipe the bore dry after application and don't allow it to dry first otherwise it will leave a residue that will need a reapplication to remove.

[Fly]

Krud Kutter for metal.What can you expect?I,m of Cajun desent (wink)

Fly

[oldred]

Ok, Krud Kutter seems to be the right stuff and although I have never tried that particular product I think it should be the same as Ospho, there are several brands around of basically the same thing. I see that Home Depot has Krud Kutter so next time I am over there I will buy some and see what it is.

[dikman]

FLY has mentioned using a bore scope. They are not necessarily a good idea, as anyone using one will probably get depressed at what they see in the bore :(. You can drop a light down and it may look pretty smooth and clean, but poke a scope down and the chances are extremely high that you will see staining, small pits and spots of rust. I doubt if any rifle that shoots BP will ever be free of it, it's just the nature of the beast.

FLY, some of the 'scopes have software that lets you take photos, if yours does try and get before and after photos. I'm interested in the outcome.

[oldred]

If these small spots revealed by the bore scope are at the bottoms of tiny pits where brushing can't remove them (that's the biggest problem with relying on solely brushing/oiling to remove rust) then they will all probability still show up after treatment and they probably will look even darker but that would be normal. The reason is that rust in pits, depending on how deeply embedded, may not dissolve away completely but this is where the Phosphoric acid solves the problems that brushing/oiling can not. The remaining rust may still be there but the difference is that while oil will only smother the rust it will remain as unchanged iron oxide and will become active again as soon as the oil film is broken, it will continue to grow every time it comes into contact with air or water -especially every time it gets wet from cleaning! However the Phosphoric acid will change the chemical structure and the remaining iron oxide (the rust) is changed into Ferric Phosphate an inactive compound that will no longer continue to grow and destroy the metal in your rifle bore, what might still be seen is no longer rust! The point is that while the bore scope will likely still show "spots" the difference, and it is a profound difference, is that these "spots" are now inactive and will not get any worse as opposed to active "spots" that will immediately start to grow in the presence of oxygen/moisture. As long as the barrel is never again neglected to the point of allowing new rust to form it will be as unlikely to form rust as a new barrel, unlike the brushed/oiled rust that is latent oxidation just waiting to jump at the chance to grow as soon as that thin film of oil is lost!