Brasso, really?

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billcarey

New member
would suggest you read a lot more.

Alum is a chemcial compound, hydrated potassium aluminum sulfate [Al(SO4)2 * 12H2O].
The class of compounds known as alums have the related stoichiometry AB(SO4)2 * 12H2O.

If you meant aluminum, it is not present in cartridge brass.

Brass is a mixture of copper and zinc (cartridge brass is 70% copper & 30% zinc).

Ammonia attacks brass with residual stress like the tension we use to hold bullets in cases.

The zinc is the main target, and lower zinc brasses are less subject to stress corrosion cracking.

With all the available things to clean and polish brass, using anything with ammonia (or ammonia compounds) is not worth the risk.

65,000 PSI 3,000 F gas in your face, and possibly metal shards from a failed case, are not pleasant.
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Yep, my bad. I didn't think most people would know AL is aluminum so I abbreviated it to alum. I suppose everyone knew I meant aluminum but you so the abbreviation wasn't a total loss. Yep again, on zinc (Zn) in brass (Br) cases, but zinc is rated the same with ammonium hydroxide so I didn't go back and change aluminum (Al) to zinc. The only reference I could find on brass case composition was two mfgs (manufacturers) that sell blanks to make cases...they are 71% brass & 29% zinc.

I posted here because I thought someone would have data that was more specific than "ammonia is bad for brass and the ammo will cause it to blow up in your face". Technically, based on no other data that is correct...eating too many asprins (Asr) is techincally correct too. If we're getting picky, Brasso contains Ammonium Hydroxide (NH3OH) which is another bird from ammonia on the corrosion scale.

I will have to "read a lot more" to get the answer to my original question. Nobody knows what the risk using Brasso really is but whatever it is they are afraid of it. So far, two or three have posted they've used Brasso for a long time and never had a problem. That small sampling of empiracle evidence based on experience says something for reality. Maybe a scientist who works in a labs and tests stuff will chime in.

Thanks for the comments from everyone. Its interesting what has developed.

Thanks,
Bill C
 
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Shoney

New member
I am reprinting this from one of my previous posts.

Any time you use acids (vinegar), bases (ammonia), or salt on cartridge brass, you can get chemical reactions that alter the brass. The key element is time, how long is the substance in contact with the brass.

The scientific reason WHY NOT TO OVER USE any compounds with these substances is:

Cartridge brass is 70% copper and 30% zinc. Chemicals and resulting voltaic cells leech the zinc from the brass at a rapid rate, the longer the contact time, the more that is leeched (key words). A small reduction in the % zinc will cause the brass to be brittle and can cause catastrophic rupture of the case.---Try this experiment: put a dab of Brasso on a case that is trashed. let it sit for an hour, then remove the Brasso. You will see the brass is now reddish. This is the copper showing on the brass that has lost zinc.

You can also see the same phenomena, spots of reddish color, in brass that has been weathered. Salts and moisture in the soil set up voltaic cells.

If you use a little Brasso in the tumbler, it is diluted thru the media, and the ammonia is probably dissipated by evaporation, causing little damage to the brass. Compare the color of the well Brasso'ed brass with new. I would wager that it will be a slight bit on the coppery side compared to new.
If you use a little Brasso in the tumbler, it is diluted thru the media, and the ammonia is probably dissipated by evaporation, causing little damage to the brass. The "acid test" (pardon the pun) is to compare the color of the Brasso'ed brass with new. If it is a slight bit on the coppery side compared to new, you are starting into the danger area.

Over long use of chemicals is spinning the roulette wheel. And with continued over long exposure, it's only a matter of time before a case ruptures.
 
F

F. Guffey

New member
I am not a member of the claims department as in I did invent/discover it, the B&M article from 1955 cautioned against using the diluted acid solution for more than 5 minutes and started at 3 minutes, they also had information on ammonia but reloaders have trouble with discerning the difference between moisture and atmosphere so that part is of little value.

Vinegar: For me Vinegar is safer, before I start I can drink it and or put it on a salad, again maximum for me is 15 minutes, this does not mean 10 minutes would not work and it is only for the worst of cases, and for the worst of cases for $14.00 I purchased 1,400 30/06 military cases that everyone passed on because they did not want to clean them for 2 weeks, anyhow I cleaned and formed the cases from/to about everything I load for,, none of the cases were made after 57 so most were fired with corrosive primers, in the old days we called vinegar 'recipe' a friend came over and said it smelled like vinegar and we cleaned ole rusty tools with it, time? did not bother to chack results for the first 5 hours, when cleaning with H2S03 we had minutes.

And I tumble with media and nothing.

F. Guffey
 
B

brickeyee

New member
Zinc and HCl are a common way to obtain hydrogen gas i the chem lab.

As you get away from the nominal 30/70 composition brass is no longer as malleable.

We rely on this malleability and work hardening in cartridges to harden the case head while allowing the body and neck to be annealed to provide a good seal in the chamber.

Anything that alters the composition of the brass needs to be used VERY carefully.

It does take time to produce changes, but given all the variables it is relatively risky at best.

Vinegar in the US has a standardized acid level (4% I think) so at least that is controlled somewhat.

The issue is how much risk is acceptable?

Some mistakes you only get to make one time.
 
L

Loader9

New member
Well Brickeyee, since you seem to have knowledge of chemistry, what are the effects of a tall oil fatty oleic diethanol amide mixed with titanium oxide on brass that we use in our guns? FWIW, CAS 68155-20-4 and CAS 66402-68-4?
 
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F. Guffey

New member
Risk, how much? I have a watch, scales, presses and micrometers, tools? I have tools, I make tools, not sophicated. enough for most but if something is missing and the weight is known before, the amount of weight that is lost can be determined.

Effect on the case, again I use forming/trim dies, turning one upside down in the press allows the neck of the case to inter the die first (up to the shoulder), when the ram is raised the case does not have many options, I expect the case to collapse like an accordion or bellows, a few cases will collapse and or split, most will form a bellows, so if I have cases that are worked hardened or the integrity of the brass is compromised for me it is not a matter of talking about it, I have tools, starting with a watch.

I make spinners, case spinners, on the worst of cases I can spin cases and clean with the 3m Green pad, then finish with steel wool, even then care must be used with cases that are not suspect, I have spun cases that shredded the mouth, neck and shoulder before they got up to speed.

And if the case has intergrity questions give them to someone that forms cases, neck them down, neck them up, blow them out etc.,



F. Guffey
 
M

Mike Irwin

Staff
I know that brass and aluminum are alloyed to make brass more corrosion resistant (Marine brass), but I can't think that it would be a good combination for use in cartridge brass.

I'd think that the aluminum would pretty much destroy the brass' ability to flex repeatedly without cracking.
 
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John Wilson

New member
Bumping this old thread 'cause I just shot some old ammo. 30years ago I had a 308W and reloaded Norma brass. I'm fairly sure I only fired these cases twice (never shot this rifle much) and would have been loaded with 4064 and have 100gn plinker bullets in them. Loads were mild (I don't use max loads) and primers showed no signs of pressure. I swapped that rifle for a 270W 30 years ago.

This week, I got a used 308W rifle to try out and as I still had this ammo, I used it. Plus also used some ex military ammo, at least 40 yr old.

All military ammo was ok, no sign of anything unusual. I had 2 out of 12 Norma cases crack, one at the head with gas coming back thru the bolt (Mauser 98). Then I decided to stop. None of the primers in the Norma brass showed any pressure signs.

I used to clean brass with Brasso. Can't be sure, but I think cases sitting in a box with traces of brasso for 30 years is probably the cause.

Anyone want some slightly used Norma brass?
 
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dahermit

New member
From wikipedia:
http://en.wikipedia.org/wiki/Brass
Brass is susceptible to stress corrosion cracking, especially from ammonia or substances containing or releasing ammonia. The problem is sometimes known as season cracking after it was first discovered in brass cartridge cases used for rifle ammunition during the 1920s in the Indian Army. The problem was caused by high residual stresses from cold forming of the cases during manufacture, together with chemical attack from traces of ammonia in the atmosphere. The cartridges were stored in stables and the ammonia concentration rose during the hot summer months, so initiating brittle cracks. The problem was resolved by annealing the cases, and storing the cartridges elsewhere.
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Who ya going to believe?
 
J

John Wilson

New member
If not brasso, anyone got any ideas why with light loads, I had 2 Norma (not cheap) cases out of 12 with cracks - one letting gas escape? Others showed some very minor bulging near the head? Ex-Military ammo, no problems. Headspace is ok. Some of the Norma cases look ok - no probs

Could the chamber be a bit oversize? But military ammo and some Norma cases show no signs of stressed cases.

I will cut the case that let go lengthwise to see what is going on on the inside and try posting a pic.
 
5

50 shooter

New member
You can also look up dezincification for more on the subject.

The way I look at it is this, why would you risk blowing up your rifle and possibly maiming yourself. Add to that, if you're at a range and your rifle blows up and someone else gets hurt you're looking at being sued.

As was said already, there are plenty of aftermarket polishes that don't contain ammonia. So there is no reason to put yourself at risk by using Brasso.:rolleyes:
 
U

Unclenick

Staff
I don't think the original ammonia has to linger. That speeds things up, but you probably just need humidity to continue the damage once you have some zinc hydroxide or zinc nitride present from the original exposure. IIRC, zinc nitride actually makes ammonia by reaction with water if some of that is left over. All it takes is time.

I seem to recall Hatcher mentioning season cracking in ammunition stores occurring after they were several years old. This would have been before brass neck annealing was first begun. I don't believe Hatcher said this, but I got from elsewhere that the damage could be caused by soldiers urinating in back corners of the underground bunkers. The 1920's were still outhouse days in many places. That would lead to bacterial breakdown of the urine, releasing a little ammonia gas. Didn't take much, it seems, which reinforces the idea that once the damage is started it can keep going. In Mr. Wilson's case, for the original exposure to have had 30 years to act on the brass could well explain the more dramatic damage.

As for other folks who've used Brasso for years, well God bless, but I'm guessing you either live in low humidity or don't age your brass in the cellar the way I've been known to do with some. There are too many variables for anecdotal evidence for one person's experience to prove or disprove the degree of risk, so I'm sticking with the military's experience and concern. They've had more statistically significant sample sizes aging at different time than I have.

One other possibility that has to be allowed for, though, is some additional source of airborne chemistry than just the original Brasso ammonia exposure. When Hatcher was in charge of ammunition manufacturing at Frankford Arsenal he set samples of brass both polished and unpolished after manufacture on the roof of the arsenal building for a year. There were a lot of chemical fumes in the air from various plants in the area at the time (no EPA back then). After a year the polished brass had corroded through but the unpolished brass was intact. It was concluded from this that the oxides formed on brass during manufacturing and annealing help protect it. This is why you don't see annealing stains polished off military brass as you do with commercial brass. It really does survive better under adverse atmospheric exposure. That may be why Mr. Wilson's military brass and not his Norma brass is still good. If so, perhaps he should have bought Lapua instead of Norma. Lapua's annealing stains are intact.
 
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P

PORTER60

New member
BRASSO

First time i have ever posted any thing on here, but into the fire i will go. I have personally polished brass rounds for about 5 years now and have experienced no problems, however i do shoot what i load and only store go to the woods military ammo. Everything else i shoot and either reload it or re-cycle it. As far as the safety of this, i kinda think it is like driving a car on the expressway. Cars are made out of metal, plastic, and verious other substances powered in large part by the burning of gasoline and oxygen in an internal combustion engine. Than we are out there with people on cell phones, texting, putting on makeup, doing drugs or drinking. Or just daydreaming or having a bad day. We try to be as safe as possible in an unsafe enviroment. Bottom line, re-cycle old brass. Load the good stuff. Enjoy your sport and shine it with what ever blows your skirt up. Ps i do use brasso when i want them to be real pretty, most of the time i dont care what they look like as long as they group tight and put meat on the table.
 
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Unclenick

Staff
Welcome to the forum.

I'd agree with you except that, unlike automobile accidents, which the local news inures us to by daily exposure, every time there's a gun accident they play up the coverage to try to support their claim gun ownership is more dangerous than helpful. So I don't see any harm in being extra careful to help protect the shooting sports. The non-ammoniated polishes are widely available for everything from case tumbling to car buffing to fiberglass cleaning. Much of it is actually cheaper than Brasso and works just fine to my eye. If you want the shine to last, add a little carnauba wax or use automotive Nu Finish, so the polishing job is protected.
 
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B

brickeyee

New member
Brasso uses Ammonium Hydroxide and Flitz just uses "ammonia solution."

Once ammonia starts attacking the brass it keeps going.
 
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