Apple Cider Vinegar (acetic acid) - will it hurt brass if used in cleaning?

[1972]

I’d like some thoughts on a brass cleaning procedure I tried today.

I’ve got a LOT of brass to clean and get ready for loading. I like working with really clean brass.

I read somewhere that an apple cider vinegar solution would clean brass without hurting it. So I bought a quart of apple cider vinegar which is labeled “5% acetic acid by volume”. I put the solution (right out of the container) into an ultrasonic cleaner I have. This unit has a heater so it heats the solution up quite hot, and of course there is the ultrasonic cleaning action as well.

I sized and de-primed 50 cases, and put them in the cleaner for 10 minute, then took them out, rinsed them well in water (several times), and dried them with a blow drier.

Then I ran them through one of my vibrating tumblers with crushed walnut shell using “PEEK” as an agent. I gave them a couple of hours in there and dumped them out.

They look new. I mean they look brand new. Inside and out, primer pockets, flash holes, everything. They look like absolutely brand new brass. I’ve never seen brass that clean.

So obviously I’m pleased with the results, BUT I’m in reviewing some threads on the internet I’m wondering if the hot apple cider vinegar can damage the brass. Some sources say if you only leave them in the solution for 10 minutes it will not hurt them at all. Other sources say this can lead to split cases and all sorts of problems.

Anybody got any thoughts on this? I’ve got hundredsof rounds of brass to clean and I do NOT want to damage it. But man, does this ever clean them! Wow!

 

[jonbearman]

What is peek? Where do you get that? I dont see how vineger could change the mettalurgy a bit un less you left it in for days and it etched the cases basically attacking the matrix.

 

[minnesota]

How hot does your temp get? degrees F please. The only thing I could come up with is the heat, but do not see that as being a problem.

 

[ChipEckardt]

For what it is worth I run for 3 minutes in distiller water as my last step. That way I know there is no residue left behind.

Chip

 

[bigedp51]

Vinegar will not hurt the brass and it is an approved cartridge case cleaner, and acetic acid is what is in the majority of liquid case cleaners. (Military arsenals use a heated 4 percent sulfuric acid dip)

I use #3 for cleaning dirty brass and then tumble. (White vinegar)


"While tumbling cases in an abrasive media provides the best finish, extremely dirty cases can be decapped first (using a non-sizing die) and then washed in one of the following solutions. The final rinse in soapy water helps prevent tarnishing. All of these methods were approved by Frankford Arsenal and will not weaken your brass.

1. A 5 percent solution of citric acid (available from your drugstore) and warm water for about 10 minutes. If your water is very hard increase the amount of citric acid. You can add some Dawn™ or Cascade™ dishwasher liquid soap (which does not contain ammonia--be careful some do), to the solution for extra grease cutting ability. Follow with a rinse in hot soapy water (Ivory™ works well) and allow to dry.

2. A solution of 1 quart of white vinegar and 2 tablespoons of salt. Soak with some agitation for 15 to 20 minutes and follow with a rinse of soapy hot water and allow to dry.

3. A solution of 1 quart of water, 1 cup white vinegar, 1/2 cup lemon juice, 1/4 cup laundry or dishwashing detergent, 1/8 cup salt. Soak with some agitation for 15 to 20 minutes and follow with a rinse of soapy hot water and allow to dry. This may leave brass with a slight pinkish cast which will disappear with a short tumble in media.

4. Military arsenals use a heated 4 percent sulfuric acid dip with a little potassium dichromate added. The solution is heated until bubbles rise slowly without it boiling and the cases are dipped into it for 4 -5 minutes using a basket of copper screening or plastic. A final rinse using plain hot water is followed by hot water with Ivory™ soap in it and the cases are left to drain and dry. Because of the use of heated sulfuric acid this method is probably impractical for home use but is given here to show what can be safely used.

Cases which have been fired several times and which show signs of carbon build up internally can be rinsed in straight paint & varnish makers (P&VM) naphtha available at any paint store. Decap, soak for 5 - 10 minutes, drain, allow to air dry and then tumble as usual. Cases will be sparkling clean inside and out but not any shinier."

http://www.frfrogspad.com/homemade.htm#Solutions

Birchwood Casey's Brass Cartridge Case Cleaner
COMPOSITION / INFORMATION ON INGREDIENTS
DESCRIPTION CAS NUMBER WEIGHT PERCENT EXPOSURE LIMITS

Phosphoric Acid – H3PO4 7664-38-2 <20 1 mg/m3
Hydroxyacetic Acid – C2H4O3 79-14-1 <7 3 ppmb
Dipropyleneglycol Monomethyl Ether 34590-94-8 <7 100 ppm a,d C7H16O3
Benzotriazole – C6H5N3 95-14-7 <1 N/Ec
Dodecylbenzenesulfonic Acid 27176-87-0 <24 N/Ec C18H30SO3
Water – H2O 7732-18-5 >41 N/Ec

 

[jraney]

i have some of the cheap corncob media, how long should i tumble brass each time. also when do i change out the media.?

j

 

[1972]

I’ll try and answer the specific questions I was asked:

JONBEARMAN
PEEK is a polish that you can use for many purposes. Here is a link to their site.
http://www.tripeek.com/
An old reloader put me onto it. It comes in tubes like toothpaste and he puts about an inch of it into a full load of new media. It really helps polish the brass up to a nice shine. He said he’s never had any trouble with it hurting the brass. I contacted the company before I started using it and they also said there was no way it would hurt the brass. If anybody has any information to the contrary I’d sure like to know.

MINNESOTA
I’m not sure how hot the water gets. This is a large sonic cleaner that has a heater built into it. It’s hot enough that it would be painful to put your hand in, but I don’t think it would scald you or anything.

JAANEY
I pretty much just polish until it's as "clean" as I want.


Based on what I have been told here I intend to try and cut the apple cider vinegar I’m using with 50/50 water. I’ll try that and see if it works as well. It would save a bit of vinegar, and I suppose the weaker the solution the better for the brass.

I’m also going to increase the rinse time and toss in a pinch of soda to help neutralize the acid.

Another idea I was given was to do a final rinse in rubbing alcohol. This would help absorb the last of the water and make it dry faster.

And I’ll use a blow dryer with the brass on a flat pan to finish up.

Just wanted to clarify again how well this worked. I honestly couldn’t believe it. That brass just sparkled inside and out, primer pocket, flash hole, everything. It was like it just fell off the assembly line at the plant where it was made.

I’m thinking that for hand gun ammunition where the brass has to “grip” the bullet, especially in semi-auto pistols, having the inside of the brass really clean is going to be a bonus.

 

[spclark]

Vinegar's great for soaking moly-coated bullets too if you want to remove that black stuff.

Soak 'em for 10 - 15 minutes, then tumble in corncob media for maybe 30 & they'll come out MUCH cleaner than you'd ever thought possible!

Re: "rubbing" alcohol - great tip, but that stuff contains water too unless you get the 99+% pure isopropyl at a hardware store. Denatured (ethanol + methanol) works just as well & may cost less depending on the brand.

As for PEEK, or any other type of abrasive metal polish & cartridge brass... what's the risk that any residual abrasive get's repeatedly blown into your barrel?

Personally I don't believe brass needs to be "new" clean every time you load it for the next go-round.

 

[fdshuster]

I've been using the old NRA formula for cleaning really dirty brass before tumbling in dry corn cob media. White vineger, small touch of salt and detergent mixed with water. Have never seen any ill effects on any brass. Cheap and very effective.

 

[jonbearman]

Thank you for the link to peek.I have many use's for it including polishing our hydro plane engine parts such as stainless and aluminum parts on the boats.I am going to try it on my brass.I have used 4 or 5 polishes on my media and have never seen a decrease in accuracy ever.I understand that people get skepticle,but I make sure the polish isnt left on the case.