Barrel cleaning: electrochemical copper and lead removal

[kwhunter]

I have read a lot of posts lately about "electronic" barrel cleaning and such. I'm not a big fan of having an electrolyte and potential in my barrels, but being an Engineer by trade and familiar with electoplating and electrostripping I decided to run an experiment to see for myself.
It is an easy setup, I won't go into details as there is tons of info online.
Anyway, to make a long story short, it works!
I used the electrolyte solution posted by others, i.e. 2 parts water (RO or distilled would be the better choice), 1 part white vinegar and 1 part household ammonia.
The potential you apply to the setup is most important: I have read about people using rectifiers, universal chargers, etc, 3-5 Volts.
From my experiment, it is best for the barrel to use a 1.5V battery; I used 2 and I ran them in parallel, therefore more 'juice'.
I metered the current through the system: it is low @ 1.5V, starts at about 100mA then as copper is removed drops steady.
I let it run for 30 minutes, took the rod out, cleaned it, replaced the electrolyte and ran it for another 30 minutes. At the end, amperage dropped to 8mA, insignificant. I would estimate that at least 80% of the copper fouling was removed.

Conclusions: if you do it, DO NOT use more than 1.5V! Higher voltage will damage your rifling, i.e. round the edges on the lands.
Make sure the barrel is connected to the Anode (+) and the steel rod to the Cathode (-)
I experimented with the batteries in series, i.e. 3 volts and the current
rised to 1A! Enough to polish your bore and round any edge!

PS: Oh, I was forgetting this: this method will not clean the gunk in your barrel, just the copper and lead. Urban legend has it that it will leave the barrel shiny... BS! Yes it will if you take your time and use the brush and the cleaning solutions as they shoul. All the black crap coming out with the electrolyte and deposited on the rod and barrel are salts and oxides from the electro-chemical reactions, not the gunk in the barrel.

Copper fouling transferred to the steel electrode:

Current reading when started

Midway, after electrolyte change

Finished

 

[Grouse Man]

Good report. I've done it as well on some really old, abused rifles. I don't believe the bore on one rifle was ever cleaned. The bore is still somewhat dark, but at least I can see light through it now!

 

[mihasic]

How did you determine the voltage limit of 1.5V?
The thing is that in those Foul-Out devices they lowered the voltage down to 300mV in the third version. I think 1.5V is still too dangerous, anyhow on the copper and steel Pourbaix diagrams I could not find any area that would be entirely secure for steel and working for copper.
I myself tried 300mV as in Foul-Out III - it does work.
Still I think for someone who takes minimal care of his firearm the method is of no value, useless and dangerous.

 

[kwhunter]

By trial and error whith whatever I had available; I have no rectifier in house to adjust voltage below 1V, but I will try nevertheless.
However, I run an experiment with steel anode and cathode vs. copper and steel; for steel, the current ran low, below 10 mA, not enough to remove any significant amount of steel. Even with a 1.5V battery it is safe in my opinion, current is dropping fast as long as there is no copper to strip from the barrel.
If you look at industrial processes, we talk amperes and up for metal stripping.
Useless it is not, because it removes copper; otherwise you may have to use hazardous chemicals to achieve the same result, and it's not entirely safe on steel either.
I respect your opinions but I disagree with your last statement.

How did you determine the voltage limit of 1.5V?
The thing is that in those Foul-Out devices they lowered the voltage down to 300mV in the third version. I think 1.5V is still too dangerous, anyhow on the copper and steel Pourbaix diagrams I could not find any area that would be entirely secure for steel and working for copper.
I myself tried 300mV as in Foul-Out III - it does work.
Still I think for someone who takes minimal care of his firearm the method is of no value, useless and dangerous.

 

[mihasic]

There's a site called "homemade firearm related products", here's what they say:
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.
I can add that there exists also a current limit - 20mA, so I fear that 10mA cannot be considered as "not enough to remove any significant amount of steel".

 

[kwhunter]

Well, to each his own I guess; the electrolyte solution they use with the industrial unit has a different composition that requites a lower voltage to run safely.
I could do a design of experiments to be rigorously documented: run 2 samples (steel and copper), weight them on the analytical scale before and after, use different setups in .1V increments electrolyte concentrations and start from 5 minutes exposure time; run 32 batches to have a statistically significant sample size and find out the optimal setting. But... cui prodest?
Like I said, I DO believe that the amount of steel etched from the bore @1.5V & 10mA is insignificant to cause any damage to the rifling and I will document it; of course if you leave it on for hours or days it can make a difference.
As far as I'm concerned I'm going to use it on my rifles, it won't damage the bore more than 1-2k rounds fired and at least removes the copper I won't be able to remove mechanically or chemically.

There's a site called "homemade firearm related products", here's what they say:
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.
I can add that there exists also a current limit - 20mA, so I fear that 10mA cannot be considered as "not enough to remove any significant amount of steel".

 

[mihasic]

I could do a design of experiments to be rigorously documented: run 2 samples (steel and copper), weight them on the analytical scale before and after, use different setups in .1V increments electrolyte concentrations and start from 5 minutes exposure time; run 32 batches to have a statistically significant sample size and find out the optimal setting.

You needn't do anything of the kind, frankly speaking - it all has already been done. Long time ago. That is why I spoke of Pourbaix diagrams. All these data are available at a simple click on a simple google.
There's no such condition that you could drive copper without destroying steel.

 

[billdick]

I have been using the outers system for years and it works great but you have to follow instructions. I use it to take the majority of the copper out and then finish with wipeout or CR 10.

 

[mihasic]

I have been using the outers system for years and it works great but you have to follow instructions. I use it to take the majority of the copper out and then finish with wipeout or CR 10.

Yes, that's what I also noticed. It works fine for stripping big amounts of copper from longly abused barrels, but still you have to use chemicals to finish cleaning. So, if I take care of my gun regularly - I simply don't need it.