Dezincification of Brass-Liquid cleaners

Cartridge companies use dilute acids to clean brass during manufacture.
Weak acids are way better on brass than alkaline substances.
Acids will react with the corrossion and grime on brass more than the brass .
Alkaline substances will react with the corrosion , the grim and the brass case all at once.
Ammonia and other amines , sulfur dioxide and nitrites is poison on brass and will harden the brass and speed up stress corrosion also. It is said to also react with zinc in the brass case.

Natural acids are better than ammonia or any alkaline cleaners .

Sulfamic acid is widely used to clean copper and brass . In a dilute warm solution it will clean cases quite well . It is the basis for denture cleaners. Sterident for one.
However you don't heat it to over 140 degreess F. because some of the acid will hydrolyse to stronger acids like Sulphuric.
If cases are badly tarnished then tumbling first in a media of some kind and then finishing off in a liquid cleaner can be more effective.
Ultrasonic cleaning works well from all reports . I have not used it myself yet however I don't think I like the alkaline ultrasonic cleaners much. They appear to me to be basicly dishwasher powders or similar substances.
I may be wrong on that but I still don't like them on brass at the moment .
Time will tell.
The other thing is that I have not heard of ammonia being present as a byproduct of burning smokeless powders or in combination with moly coatings either.
Generaly the combustion products for a single base powder are carbon dioxide, and nitrogen oxides. Under some conditions, methane, carbon monoxide, irritating aldehydes and carboxylic acids, and hydrogen cyanide may be formed.
 
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I guess I though everyone had heard of M30 sorry about that. What I am talking about is M30 cleaner and degreaser it is a liquid soap. You can get it a rual king and most auto stores. It is good for a lot of things,give it a try.
 
acetic acid

My brass looks like it has Stress corrosion cracking. Having never knowingly used ammonia for cleaning, then i would have to quess that the brass was damaged by the NRA mix?:confused: But Admiralty Brass containing 70% copper & 29% zinc + 1% tin and arsenic is resistent to acetic acid. Copper alloy 260(rifle brass) is made of 70% Copper & 30% zinc with small % of tin & arsenic if my internet search is correct?:confused: Maybe the brass just died of old age. :D This brass may have been from a batch that was left soak in the NRA mix overnight by mistake. Great info Gentleman, thank you.
 
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243winxb said:
My brass looks like it has Stress corrosion cracking. Having never knowingly used ammonia for cleaning, then i would have to quess that the brass was damaged by the NRA mix?:confused: But Admiralty Brass containing 70% copper & 29% zinc + 1% tin and arsenic is resistent to acetic acid. Copper alloy 260(rifle brass) is made of 70% Copper & 30% zinc with small % of tin & arsenic if my internet search is correct?:confused: Maybe the brass just died of old age. :D This brass may have been from a batch that was left soak in the NRA mix overnight by mistake. Great info Gentleman, thank you.
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There is a few reasons why it may be suffering cracking.
Excessive hardness from never being annealed.
Then being loaded with old expander ball dies.
Old brass may have been fired with a primer containing mercury at some point.
Ammonia from bore solvents not properly cleaned from the barrel or chamber contaminating the brass.
Liquid case cleaners containing Ammonia.
Crap quality brass that has too much zinc or impurities in it.
Brass left dirty for long periods of time.
Age hardening complicated by some of the above leading to stress corrosion.
All of or a combination of the above.

Its a bit like , why is your neighbours car all rusted out but your car of the same age and model is still fine ?
Well you looked after your car and your neighbour parked his car at the beach every weekend.
 
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j.higdon said:
I guess I though everyone had heard of M30 sorry about that. What I am talking about is M30 cleaner and degreaser it is a liquid soap. You can get it a rual king and most auto stores. It is good for a lot of things,give it a try.
Click to expand...

What is the active ingrediants in M30 cleaner ?
 
243winxb said:
My brass looks like it has Stress corrosion cracking. Having never knowingly used ammonia for cleaning, then i would have to quess that the brass was damaged by the NRA mix?:confused: But Admiralty Brass containing 70% copper & 29% zinc + 1% tin and arsenic is resistent to acetic acid. Copper alloy 260(rifle brass) is made of 70% Copper & 30% zinc with small % of tin & arsenic if my internet search is correct?:confused: Maybe the brass just died of old age. :D This brass may have been from a batch that was left soak in the NRA mix overnight by mistake. Great info Gentleman, thank you.
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What is the ingrediants in the NRA mix you used ?
I remember an old NRA article way back that put forward a salt and vinegar formula is that it?
 
Just off the top of my head I'd say that Admiralty brass might have been put together to resist corrosion and general nastiness that might have been experienced in salt spray on Royal Navy ships back when shiny was considered nice. It's likely to resist corrosion that normal brass wouldn't like. Ocean water is nasty stuff for metals to try to live in.
 
Larry Elliott said:
Just off the top of my head I'd say that Admiralty brass might have been put together to resist corrosion and general nastiness that might have been experienced in salt spray on Royal Navy ships back when shiny was considered nice. It's likely to resist corrosion that normal brass wouldn't like. Ocean water is nasty stuff for metals to try to live in.
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You are right Admiralty brass is higher up the nobility list than red or yellow brass which is similar in nobility to cartridge brass.
This makes it less suceptable to wasting from electrolysis and more able to be protected by sacrificial anodes ( usually zinc) .
 
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I use the NRA formula listed above. Doesn't harm brass soak 1-2hrs sometimes.

Do not use DAWN dishwashing liquid contains ammonia.

Do not use ammonia or bleach.

Use a good powdered laundry detergent is slippery er than dish soaps. Do not use ones with color safe bleach or whiteners oxdol etc. Do not use oxyclean etc. Just inexpensive laundry soap and the vinegar salt and water mix.
 
J. Valentine said:
What is the ingrediants in the NRA mix you used ?
I remember an old NRA article way back that put forward a salt and vinegar formula is that it?
Click to expand...
1 pint of water, 1 cup of white vinegar, 1 tablespoon of salt, and 1 teaspoon of detergent". Mix the solution in container. Shake 10 minutes with brass. Rinse 10 minutes clean water. Sun dry. This was printed in an NRA reprint of loading for the 45 acp many years ago.
 
You have to read what was said in #135.....

Rifle mag. The letter was quite detailed, that there IS a small amount of ammonia produced on firing, & that one of the easiest ways to neutralize it was to tumble(if the brass isn't too tarnished) the brass w/some powdered citric acid. This DOES change the appearance of the brass somewhat, but it isn't unbearable to witness. Now as for the "annealing" side of it, it was stated that having this stress corroson cracking of brass, handloaders automatically think, "Hm, I guess I need to anneal this brass!!" The author said this was basically a WASTE OF TIME as NO annealing will reverse this condition, only the aforementioned tumbling, or, I suppose, a bath w/some citric acid in it would cancel the condition. On another note, those who DO use ammonia cleaners, even after patching out, may be subjecting the brass to this kind of contamination as a result of storage in the safe, because not ALL the chemical is gone, and through capillary action, the ammonia will migrate to the chamber & elsewhere, and the brass only has to come in contact w/a small amount to be contaminated, especially in a tight-necked benchgun. One of the easiest ways to combat this would be to use a Caplug on the muzzle. Just measure the muzzle, subtract .020, thats the size Caplug you want, then store the rifle right-side up, resting ON the Caplug, & all the junk runs down into the Caplug to be wiped out & neutralized when used again( No, I do NOT have any financial, or other, interests in Caplugs!!:D). I feel sorry for those guys who are forced to store their rifles upside-down, because all the stuff runs down into the triggers & other tasty morsels.....:D:eek::rolleyes::rolleyes:;):D
 
Oooooooooooookkaaaaaaay.........

I finally got the recipe for cleaning (not de-zinc-ifying, brass) as follows.

1/4 cup vinegar
1 Tbsp salt
1/8 oz.(up to 1/4cup) dish liquid(somone specified which brands to be avoided)
1/2 gallon water
Immerse & agitate brass 3-4 minutes
Dump mixture when done, rinse in clean water
May then chage water, agitate then dump water
In warm weather, can then spread on concrete until primer pockets are dry
(brass warm) or, can put in oven on cookie sheet @ 100F for 10 Mins. or less, 'til dry.;)
 
GM top engine cleaner

I'm kinda wondering if GM top engine cleaner can be diluted and used in a ultrasonic for case cleaning. Any idea if it will hurt the brass?
 
Just my worthless $.02 worth...but I believe that brass, over time, suffers from something similar to but not exactly like dissimilar metal corosion. Due to different electrical charges, the zinc and copper tend to migrate towards like molecules (zinc to zinc, copper to copper) ...causing the brass to become brittle.
Mark
 
Rflshootr said:
I'm kinda wondering if GM top engine cleaner can be diluted and used in a ultrasonic for case cleaning. Any idea if it will hurt the brass?
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It might or might not hurt the brass, but since the Top Engine Cleaner has a lot of organic solvents in it you might get a nice explosion if there's any kind of sparking from the ultrasonic cleaner. In the lab I worked in we only used water based solutions in the ultrasonic cleaners.
 
Nice to see some historical discussion here.

Stress Corrosion Cracking of Cartridge case necks, at least on first firing, was discovered by the British Army in India during the 1920's.
The cause there was found to be ammonia vapors in the air after the Monsoons.
The phenomena had occasionally presented itself before on a much smaller scale when Calvary troops stored ammo in the stables, ammonia vapor rose from horse dung.

Straight cases seldom showed cracks on first firing, but bottle neck cases did frequently.
The reason was stress on the brass during the neciking down process leaving microscopic surface cracks that could spread enough to give the ammonia something to work on.
Stress relieving the neck and should of .303 brass was difficult at that time because the shoulder was formed after the charge was inserted. Earlier .303 used a compressed Black Powder Pellet that resembled a solid rocket motor to control burn rate, Cordite strands in bundles also required the shoulder to be formed after the charge was inserted.

I once broke down some degraded FNM 7.62 NATO ammo for components.
The powder had a strong ammonia smell to it, like cat urine.
I put the powder in an old steel powder can in a drawer and a couple of months later I found the lower half of the can had turned to red dust. Every steel item in the drawer was badly rusted.
The gilding metal also peeled away from the steel jacket bullets.
Examing the cases I found pinholes in most of them, corroded from the inside out. I trashed the whole mess.

To polish the outside of cases I use white polishing compound,with alcohol as the carrier. Just wet a cloth with alcohol and rub on the bar of compound then polish by had. Afterwards I rub the outside with a rag moistened with penetrating oil and wipe dry.
I got some red and brown jewelers rouge to use for this now, less likely to embed.
 
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