Author Topic: Corroded brass - how to clean  (Read 6242 times)


  • Guest
Corroded brass - how to clean
« on: October 29, 2012, 01:58:48 PM »
I have over 500 brass cartridges that were given to me.  They are structurally sound but have a thin layer of pinkish corrosion on them due to being left in a container that housed pool chlorine tablets.

My pics are about as clear as I can get them so please bear with me.  Hope they are OK.

First pic is of corroded case. Very gritty.

Second pic shows partial cleaning using silverware polish and a dremel with a soft pad attached.

Last pic is case completed with polish and dremel.  Looks brand new. Smooth as silk.

There is no way I clean over 500 cases using the dremel tool way.

I tried some polish in my tumbler but it did not work.

Is there anything else I could try like coke or pepsi or some other liquid that I could soak the cases in.  Any help greatly appreciated.  Thanks

Offline GhostWarrior

  • I'm very humble, you can ask me.
  • Administrator
  • Hero Member
  • *****
  • Posts: 3039
  • Benefactor & Life Member NRA
Re: Corroded brass - how to clean
« Reply #1 on: November 07, 2012, 09:32:04 AM »
I actually have no idea how you could go about cleaning that many rounds. I have a couple guesses that way or may not work. First try soaking them in Lemon juice or Baking soda (Not powder): Actually I thought I would check my idea on-line to make sure I was saying it correctly and came across this on: You'll Need
  • Plastic or glass  container
  • Hot water
  • Dish soap
  • Phosphoric  acid
  • Baking soda
  • Used brass gun  cartridges
Read more:  How to Polish Gun Brass |
      1) Wash the used brass cartridges in a very hot soapy solution. Agitate the  containers for a few minutes to ensure the solution has an opportunity to clean  residues that can affect the next step in the cleaning  process. Rinse the cartridges in clean, hot water and  drain.     
     2) Add more clean, hot water to the same container with the brass cartridges.  According to the amount of water you are using, add ˝ teaspoon of Phosphoric  Acid per gallon of water to the container. The addition of the phosphoric acid  will generate a chemical  reaction which will eliminate any remaining residual buildup of discharge contaminants that may be left after the initial soapy solution. This solution  will clean the cartridge inside and out including primer  pockets.

      3) Pour baking soda into the phosphoric acid solution to stop the cleaning  activity. Drain the cartridges from the solution and rinse with more hot water.  The cleaning process is complete.

      4) Examine each cartridge after cleaning. The phosphoric acid solution will have  cleaned any residual powders and material left over from the previous shot. The  solution will also highlight any corrosion that may be present in the  cartridges. The corrosion will show up as a highlighted copper look to the brass. If after wiping the cartridge down the corrosion is still  noticeable, you should scrap the cartridge as unusable in the  future.

Read more:  How to Polish Gun Brass |

Tips & Warnings
  • The phosphoric bath has no time limit. As the chemical reaction acts only on  the residues left behind and not the brass, you will find that the brass will  become clean almost instantly.
  • Because of a chemical reaction called “passivation,” the brass is actually  made stronger after the acid bath.
  • You can save the solution by not adding the baking soda when finished. The  solution will last a long time, and can be used for multiple cleanings.
  • The phosphoric solution is environmentally safe
Read more:  How to Polish Gun Brass |
Here is another way:

Legalize: I personally have never tried any/either of these ways to clean brass, so if you try either of these you do so at your own risk. I simply found the ideas and posted them as suggestion. I am certainly NOT advocating either of them. I do know however that Baking Soda and I think lemon or lime juice will shine up brass. Or at least Baking soda and something else, I know it was years ago back when I was in the High School Band and couldn't afford Brasso. So I'm thinking through in some cleaning medium and add both the Baking Soda and the lime juice and let it run for a couple or 6 hours.
              If it were me I think I would try the dish detergent and hot water in a jug, shaken, not stirred. Then rinsed off, let dry, and then fill up my tumbler with crushed Walnut shells and some one of the other suggestions and see how that works. But that is me, what you try is up to you.
If at first you don't succeed, then Skydiving is not your sport.

Welcome Home every Veteran and active Service personnel and Thank you from the bottom of my heart for your sacrifice


  • Guest
Re: Corroded brass - how to clean
« Reply #2 on: November 07, 2012, 09:50:34 AM »
Thanks for all the suggestions. To err on the side of caution I trashed all the bad brass. I also learned that S&B is not brass but steel plated with brass so I got rid of that too.

Offline DeeDubya

  • Full Member
  • ***
  • Posts: 214
  • NRA Life Member
Re: Corroded brass - how to clean
« Reply #3 on: November 14, 2012, 02:05:15 PM »
For some reason, brass does get brittle with age. Also you might notice that fingerprints seem to etch into the brass. My tried method (although maybe not environmentally sound) of storing brass is this:
I purchase wide mouth plastic containers that are suitable for storing solvents. Pitch in sorted brass, mark the container and then pour in paint thinner (naptha, the cheapest) just to cover the cases. When I come in from shooting I immediately sort the brass and store it like this. It will not discolor or change in any other way simply because the naptha locks out oxygen. Oxygen is the culprit in metal deterioration like rust and here, corrosion.
When I'm ready to load, I pour off the naptha into another container to reuse and dump the brass onto an old towel to let it dry. The naptha will flash off in an hour or so especially if left in the sun. After tumbling, the cases will be extra bright as well as completely oil free.
CRA / NRA  Protect Your Rights
"You can easily judge the character of a man by how he treats those who can do nothing for him."
~ James D. Miles

Offline Angryvikingman

  • Senior Writer/Editor/Moderator
  • Hero Member
  • *****
  • Posts: 949
  • Si Vis Pacem Parabellum
Re: Corroded brass - how to clean
« Reply #4 on: November 14, 2012, 05:35:07 PM »
Cleaning dirty brass? Can you not use a case polisher and some aggressive media?