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Copper Fouling Removal

The “Ammonia Solution”
The typical “household ammonia” is only 3 percent and does not work very well as a copper remover. However, to remove copper fouling you can use use straight “strong ammonia” (9 – 10 percent) carried by many janitorial supply houses and hardware stores. My local ACE hardware carries the 10 percent janitorial strength for about $1.50 a quart and it works great straight, followed by a thorough cleaning with Ed’s Red. Run a wet patch through the bore and allow to sit for about 5 minutes and proceed as usual. Don’t use a brass bore brush or jag! I have seen no scientific proof that the use of ammonia in any strength will harm bores, IF the bore is thoroughly cleaned with bore cleaner after using ammonia to prevent after rust.

If your local ACE hardware store doesn’t stock the “10% Janitor’s Strength Ammonia,” they can order it for you from their master order book. The stock number for the 1 quart size is ACE10183.

If you are worried about its high strength, you can bring it down to the 6 – 8 percent ammonia content of most commercial copper removers by cutting the janitor’s strength ammonia with some K1 kerosene or water–try 3.5 to 4 parts 10% ammonia to 1 part water or K1 kerosene. This seems to have little, if any effect, on its copper removal abilities.

Straight 28% ammonia (CAS#7664-41-7) followed by a thorough cleaning with Ed’s Red can also be used but 28 percent ammonia may be difficult to get and is VERY strong stuff and potentially aggressive on metal.

Some notes about Ammonia. Ammonia won’t harm the rifle’s metal, the pH is way down there for even 10% but as you get into stronger solutions (> 10%) the pH becomes basic ( >7 up to 14) and is caustic. The problem comes from ammonia being hygroscopic and folks not cleaning it all out of the bore and the attracted water then causes rusting. [As a test I left a polished mild steel strip in straight 10% ammonia for 48 hours and saw no noticeable corrosion or etching.]

Thanks to Roger Rothschild, Chemist, for this information.

…and an Improvement–“Humpy’s White Bore Cleaner”

This modification of the “ammonia solution” thickens the liquid and helps to keep it in the bore for more efficient cleaning. You can if you like omit the 1-part sudsy ammonia

2 parts – 10% ammonia,
1 part – standard household “sudsy” ammonia (optional)
1 part – Ivory liquid dishwashing detergent (It has been reported that “Formula 409” can also be used though the resulting mixture is probably thinner.)

This formula yields about a 6.5 percent ammonia solution. If you omit the sudsy ammonia the solution is about 7.75 percent.

Thanks to Mark Humphreville for this solution

Electronic Fouling Removal

A Caveat

The Outers FoulOut operates at a very low voltage (.3 V – three-tenths) at the cleaning electrode. Higher voltages can start to etch the bore, and even at the lower voltage the Outers can do so if there is rust in the bore. While the simple designs given here can be used safely there exists the possibility of bore etching due to their higher voltages. This is a particular concern if you use the Outers solutions. The electrical problem with all the home-brew series current limited (by the short indicating lamp) devices is that they apply voltages that will start taking iron into the solution, according to the FoulOut patent information which has expired. This aspect of the circuitry deceives those without electrical backgrounds. They look at the batteries or the wall adapter voltage used to operate a FoulOut and assume it must be safe to apply that much voltage between the barrel and the rod. Not so. The voltage regulation schemes inside a FoulOut are designed to hold a 0.3V limit regardless of how many volts the power supply has.

A Basic Homemade Electronic Copper Fouling Remover

Most shooters are familiar with the Outers FoulOut ™ electronic copper fouling remover that will remove unbelievable amounts of crud form a “clean” barrel. It is quite easy to build your own simple version of this handy device.

A Current and Voltage Limited Homemade Electronic Copper Fouling Remover
While this design is a little work to build it provides current and voltage limitation to prevent etching. Designed for use with the Outer’s type solutions it should work with the vinegar/ammonia formula. You can download the article which is a 340K PDF document, by clicking here.

Make your cleaning solution of:

1 part white vinegar
1 part household ammonia (3%)
2 parts distilled water

I am currently researching a better formula.

It is best to remove the barreled action from the stock for cleaning. For best results clean and then degrease the bore with a commercial “gun scrubber” or automotive brake cleaner. Plug the chamber with the rubber stopper and carefully insert the rod down the bore and insure it is seated in the hole in the stopper. Using a dropper or a syringe fill the bore with the cleaning solution and the attach the black wire to the rod and red wire to the gun. If the gun is dirty the flashlight will glow but not at full power. If the flashlight immediately glows full power the rod is not centered in the bore and has caused a short. Allow the unit to work for 45 min or so, disconnect the leads and carefully pull the rod out of the bore. The accumulated copper fouling can be removed from the rod with fine steel wool. Drain the barrel, remove the stopper and dry the bore and chamber. Run a couple of patches with bore cleaner on them through the bore and chamber to prevent any after rust and you’re done. Those of you with a background in metal plating may want to contribute your own solution recipes. Send them to me by clicking here.

36″ long TIG welding rod in stainless steel are available from local welding shop. Get 3/32″ and 1/8″ diameters at a cost of about $1.25 each. Ideally you want a rod about 1/2 to 2/3 of the bore diameter.

Thanks to Robert Schaedel, et. al. for this tip.

Some Interesting Information.
Just for those of you with curious minds, the Outers CopOut Plus solution contain approximately 0.6 percent cupric acetate and 2.5 percent ammonium acetate (3.62 grams/ liter of copper acetate and 38.5 grams/liter of ammonium acetate) in distilled/deionized water. The LeadOut Plus contains approximately 2 percent lead acetate and 5 percent ammonium acetate (6.50 grams/liter of lead acetate and 38.5 grams/liter of ammonium acetate ) in distilled/deionized water. A good basic solution for either would be

Copper Solution
562.3 grains Ammonium Acetate
51.3 grains Copper Acetate or 58.3 grains Cupric Acetate Monohydrate
Add distilled (or high megohm deionized) water to make 1 Qt.

Lead Solution
562.3 grains Ammonium Acetate
95.0 grains Lead Acetate or 110.8 grains of Lead Acetate Trihydrate
Add distilled (or high megohm deionized) water to make 1 Qt.

Note that since the Outers FoulOut unit limits the voltage and current in the electrolysis process and runs at about .3 volts (3/10 volt)– at typically a max of about 20 milliamps. If the vinegar/ammonia solution described for the homemade unit is used in an Outer’s unit the cleaning process will be much slower because the solution does not contain any ions of the lead or copper (one reason the homemade unit runs at a higher voltage).

Possible sources for these chemicals in small quantities are:

Post Apple Scientific, Inc.
Sigma-Aldrich (800-325-3010)

This company lists 100 grams of Copper (II) Acetate for about $19 and 500 grams of Ammonium Acetate for about $17. If you assume $1.00 per gallon for distilled water, you can make the solution for copper removal for $1.60 per quart. This does not include shipping costs on the chemicals.

The Science Company

The following is from Outer’s Q&A page.

Q. Why has the solution become discolored during use?

A. You need to check the solution about every 30 minutes to see if it has changed color. Pour all the chemical into a clear container to see if there may be a color change. Sometimes there may be sediment or a color change but it isn’t apparent by simply looking at the chemical in the barrel.

If chemical is orange or orange/brown you may have some rust. If chemical is black you may be lifting iron from the barrel or its oxidized copper salts. It could also be some powder fouling being removed from the barrel. The unit may have been on too long without checking the solution color often enough.

Black/Gunky chemical could mean that in the first 30 minutes you hit a lot of lead and lead started to settle set the bottom of the barrel as well as on the rod. It could also mean the unit was left unchecked too long and rust has formed.

Green colored chemical could mean that you may be pulling out iron, blueing or rust. Sometimes new barrels will have blueing and its removing that.

Q. What do I do if the chemical changes color?

A. Dispose of the chemicals according to local and state laws. Clean the barrel using regular gun cleaning methods. Degrease the barrel and rod with Outers Crud Cutter. If you can’t find Crud Cutter, you can use Birchwood Casey Gun Scrubber or household rubbing alcohol. On a scale of 1 to 10, alcohol rates as a 2 and Crud Cutter rates as a 10. After cleaning and degreasing the barrel and rod, start the Foul Out III according to the instruction book. [Automotive brake cleaner is the same as the Birchwood or Outers products and cheaper. – Fr. Frog]

Q. The unit isn’t cleaning fast enough.

A. To speed up the process, after cleaning for two hours, change the solution and you should obtain faster results.

Q. Can I Use Cop Out Plus and Lead Out Plus with my Foul Out II Unit?

A. Yes, You can use the Cop Out Plus and Lead Out Plus with Foul Out I and Foul Out II units. Because these are more potent chemicals than regular Cop Out and Lead Out, the customer needs to be more cautious and check the chemical for changes more often. The new chemicals will clean faster than the old.

Military Copper Fouling Removal Solution (c.1917)

Described in the US Military publications for the 1903 and M1917 rifles was the following “heavy duty” copper removal formula.

1 oz Ammonium persulfate
200 grains Ammonium carbonate
6 oz 28% ammonia
4 oz water

Finely grind the persulfate and carbonate, dissolve in the water and then add the ammonia. Allow to stand for 1 hour before using. Plug the breach and slip a piece of rubber hose over the muzzle. Fill the cold barrel and the section of hose with the solution. Allow to stand for 30 minutes. Dump the solution and clean the bore normally and oil.

Mac’s Red
A modification of Ed’s Red that is claimed to remove copper fouling was developed by Richard McQuisten and published in The Cast Bullet #113, Jan-Feb, ’95.

1 part Dexron II, IIe or III Automatic Transmission Fluid
1 part K1 Kerosene
1 part Mineral Spirits or Stodard Solvent/Varsol
1 part Acetone
1 part GM Carburetor/Upper Cylinder Cleaner

Oxynate S
Brownells sells a product called Oxynate S (pn 082-029-016) which is used to remove copper from bluing tanks. It can be used straight or mixed into a bore cleaner, say about 5%, to remove copper bore fouling.

Thanks to Ken Mollohan for this tip.