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Electrolytic copper removal

8K views 5 replies 3 participants last post by  unclenick 
#1 ·
Noted a link in another thread about use of electric means of copper removal from barrels. The following link was given: http://www.surplusrifle.com/reviews/copperout/pdf/makingthesurplus2.pdf. Well being cold today and with not much else too do decided to make up one of these apparatus. I made several modifications too the overall apparatus but keep the electrolyte formular the same. Rather than using two D-cells I used a 12 volt DC battery charger for the power source. Unbelievable how much gunk came out of an old take off barrel. Sure glad I used this old barrel as a learning tool. Definately will need modifications before using on a good firearm. Main issue is the boiling off of electrolyte. I used a hose on the barrel end but next time will use a longer one along with plastic tee too drain into seperate vessel. Suspect I let it run too long (25 minutes) but it was impressive the amount of junk that came bubbling out. After draining everything and giving everything a good wash down in hot water proceeded too clean the bore by regular means. I tried some Montana Extreme 50 BMG copper remover first -- nothing just a brown tinted patch. Next used bore brush with Hoppe's No. 9 and patches with them coming out as you would normally expect.

Don't know if there are any chemists out there who are brother shooters but my curosity has got the better of me. Just what is happening in this electro/chemical reaction? It apparantly does remove the copper fouling but in what form? Its not plated on the rod like you'd chrome plate something.

I have several other take off barrels too experiment with so will try different modifications determining what works the best.
 
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#2 ·
The cleaning action should plate the copper on to the rod, but you were using 12v not the 3v recomended. I would think that much of the copper was stripped off the barrel surface and was in suspension. The ammonia will dislove some of the copper but not all of it.

One way to really check on how the system works is to check a barrel with a bore scope before and after cleaning.
 
#3 ·
I plan on lowering the voltage on the next barrel. Since I've acquired around dozen take off barrels from one source or another over the years should have plenty of gunnie pigs for experimentation. Did notice that patches went through the barrel much easier with less snags than the patches run through before starting.

Wouldn't mind having a bore scope but from my research there mostly good for looking at bores after the fact. Trying to determine if a barrel will shoot or not with one is wasted energy. Last time I knew there pricing was nearly a grand but its possible they could have come down.

Debating whether too try this on some old sewer pipe military surplus barrels. Would be interesting to see what happens concerning cleaning up the bore and improvements in accuracy.
 
#6 ·
The Foul Out's patent has expired, but reading it is a valuable learning tool.

First, it is perfectly possible to etch a plain steel bore with these homemade systems. The Foul Out patent explains that only limiting voltage to 0.3 volts will prevent this and that is what theirs does. To work at that low voltage you need to use something better than just ammonia and vinegar. The patent gives the original formula that provides both ammonium acetate and the acetate salt of the metal to be etched so as to get those correct ions in place in the conduction path. Outers later revised it with surfactants to better remove the powder fouling that is between layers of copper.

I designed a proper 0.3V regulated device for Father Frog awhile back. You can download my design, here. The electrolyte will not boil. It will not remove steel unless there is rust in the bore when you start. If the solution turns brown, STOP because there was rust in the bore and the presence of those iron ions is now carrying iron to the center electrode. Stainless is probably immune to the etching problem because of the same chromium oxide surface layer it has that prevents rust.

The original solutions from the patent below. I like to add a drop of Kodak Photo-Flo to them for better wetting. Dawn dishwashing liquid would probably work, too.
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.


Back about 1989 the Cast Bullet Associations publication, The Fouling Shot ran an article on a flashlight voltage cleaner and the author cleaned a chrome moly steel bore with it. A few days later it was coated in rust because the surface etching had activated the steel. I can't recall his particular solution, but by then Outers had warned them off by virtue of their patent still not being expired at the time, so the recommended against the thing on both scores.

Hope this helps.
 
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