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243winxb
01-05-2009, 10:00 AM
Is this Recipe safe to use? :confused: 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. I have used it for many years for rifles. But have had problems with brass becoming brittle in some 223 rem. http://www.hghouston.com/coppers/brass75.htm I found this also http://www.6mmbr.com/ultrasonic.html I would love to hear from a Chemist on the subject. Or anyone else. Thank you in advance.:)

Larry Elliott
01-05-2009, 04:00 PM
After skimming the article on dezincification and preferential dissolution I think I'd stay away from vinegar which is just dilute acetic acid, or any other acid, weak (like vinegar) or strong (like hydrochloric, nitric, or sulfuric). Having nice, shiny, like-new-looking brass might be nice, but if there's ANY chance that the cleaning might weaken the brass I'll take scruffy looking brass anytime. I just tumble my dirty brass (from any self-loader, or revolver) in corn cob. That cleans the stuff off the outside that could scratch dies which is all that really matters. Brass from other rifles is tumbled when it begins to look too bad. Spiffy-clean cases don't shoot any better.

If you remove the zinc from brass you've got copper, if you only remove part of the zinc you've got weakened brass. I sincerely doubt that brass except for specific applications has any arsenic added since arsenic is nasty stuff. Kill ya dead nasty in fact, after it's made you sick for awhile too.

Yes, I used to be an analytical chemist up until just over ten years ago when I retired and life became much better.... :D

brian roberts
01-05-2009, 07:07 PM
to leave that in there for 10 minutes. If the water is warm, or hot, just agitate it, or shake it just for a minute or two, then dump the mixture & change the rinse water after a minute, allowing the new water to sit w/the brass inside for 5 minutes or so, then dump again. Once you have it clean, future tumbling should be done w/a tablespoon of powdered ascorbic acid (vitamin C) in a large tumbler, 2-3Tsp. in smaller sizes. By not using the ascorbic acid, you actually shorten the life of the brass, which all the tumbling, and/or annealing won't save, because of the ammonia which is inside, as a result of the chemical being produced by combustion.

Larry Elliott
01-05-2009, 11:07 PM
Ammonia is produced on combustion of smokeless powder? It's amazing that I've got cases that are 30 years old that are still just fine if there's all that ammonia in them from firing. I'd like to see the chemistry of that one.

brian roberts
01-11-2009, 10:36 PM
there was a quite lenghty "letter to the editor" in either Rifle or Handloader a few years back, I'll see if I can find it. It has to do w/what is termed "stress corrosion cracking". It made a believer out of me when I found about 45-50% of some deuces I had reloaded, & unfired since about '75, that had vertical & radial cracks on the necks. Say, after being an analytical chemist in your past life, why don'cha drag out some of the stuff you used/had in the past, & do some analytical chemitizing for us & report your findings??? Maybe those cases you have are so fine because you didn't leave them LOADED for 30 years; I mean, it IS called "STRESS corrosion cracking", maybe you can load up some & leave 'em loaded for the next 30 years & get back to us on your practical, if not chemical, deductions. After being a chemist, it ought to be fairly simple to do some chem. analysis & give us your findings; I don't have the materials or training or inclination, but it shouldn't be rocket science. I read the letter & thought, "Hhmmm, let me go check some of my stuff to see if......". And BINGO!!! what the guy said would/could happen, had happened to me! So, I started to use the technique he advocated, as he also said that annealing would, in this case, NOT cure the problem. There are numerous chemicals released upon firing, & I was once told that when the rifle is fired those chemicals & dissimilar materials coming down the bore was something like a mild battery acid following the bullet. But hey, I'm not a chemist (& I don't play one on TV:D) I just try to take care of my stuff, because I can't just replace things on a whim. Replys like yours tend to make people NOT offer information; I read the letter & it made sense to me, so I didn't start a pissing contest with the author. :rolleyes::D SEEya.

Larry Elliott
01-12-2009, 09:23 AM
Uh, sure Brian. ;) Chemistry isn't like what's shown on the tv, and I doubt that if I loaded some ammunition up now that I'd be around in 30 years to see what it looked like anyway. If someone would like to supply me with a nice lab, a half million bucks could probably cover it for a short while, and some ambition I might give the problem a look. Too old and too retired to do chemistry now. :eek:

Loaded ammunition can have neck problems because for whatever reason the necks tighten and age harden around the bullets. I'm not a metallurgist, but I'm sure that if there's one lurking out there they could give us a simple answer. I've fired old (at least 20 years, maybe 25) factory loads that produced about 50% splits on firing. Since I didn't look at the necks under any sort of magnification before firing so don't know if that would have shown anything.

My theory is that brass like some aluminum alloys age hardens. When it's under stress from being loaded for a long time and trying to return to it's previous size which it can't because of the bullet in the way it cracks. No chemistry is involved it's due to the nature of the material.

I'm not trying to start a pissin' match either, but there are a lot of things offered in print and on the internet that sound good, and may not hurt, but whether they help or not is open to question. Most people don't have 30 year old loaded ammunition lying around, although old military ammo seems to work just fine without any problems. I've got some early 40's military 9mm made in Canada that fired fine when it was at least 40 years old, and the cases were reloaded several times with no problems.

The only thing I can imagine that would cause brass to fail if fired and not reloaded would be mercuric primers. Mercury and copper will form an amalgam that will ruin cases. Most modern powders and primers while not being completely innocuous don't produce byproducts that are harmful to cases or the bore.

brian roberts
01-12-2009, 02:47 PM
and in my mind, I touched on all the things you mentioned, & I have seen old military ammo fired w/no ill effects, either. But I also considered this: If it was never fired & reloaded, & survived the first firing, then why would once fired & reloaded brass suffer from the splitting & cracking? I know what you mean about age hardening & tension, as well as some splitting on the first firing from overly old ammo; but, as a chemist(or ex-chemist), what about the paper test-strips, wouldn't ammonia show up on one of those?? If you took a fired case, w/o cleaning, put some water inside and let it sit overnight, then dipped the test-strip in there, would the presence of ammonia, or acid, be detected then?? And I'm not trying to put you on the spot, here, I mean, it made sense to me, and I was hoping that somebody like you could come along & try it out. The explanation the fella gave in the letter made sense at the time, it was VERY well written, & I haven't been able to find it, its in the piling system, somewhere. The presentation made sense the way it was laid out. I have started using it myself, & keeping an eye on it.

Larry Elliott
01-12-2009, 03:15 PM
Brian, do you have any idea when that letter was published. I've got RIFLE and HANDLOADER back to the early 70's so if I had an idea where it was I'd read it and be able to comment better.

About all that could be told from using pH test strips would be the pH (acidity or basicity) and wouldn't tell what was producing the raised or lowered pH. Smokeless powder will produce acid if it decomposes from age or too high storage temperatures, and it would seem likely that if powder decomposed inside a loaded round that the results would not be pretty.

Nitric acid, from the decomposition of the powder, eats copper for breakfast, lunch, and dinner. Back in the old days when most powders were packed in containers made from metal or ones that had metal parts it was common to find rusting on the metal when the powder began to decompose. I could certainly see the powder starting to decompose if ammunition were stored at high temps. That could/would attack the case and produce failures on firing.

243winxb
01-13-2009, 07:36 AM
A metallurgist has said that "stress corrosion" happens when ammonia is used on brass for cleaning. http://www.thehighroad.org/showthread.php?t=417310 But is ammonia formed/created with combustion of powder:confused: Sure would be great to know. My brass was cleaned in the NRA mix and stored for around 20 years. On firing 4% came apart. The photos are of some that came apart when neck sizing using standard dies where the brass is overworked. The expander button pulled the necks apart.I am guessing they were already cracked from firing. The inside of some brass necks will turn green if let stand for a long time after firing. Some chemical must be attacking the brass i would think? So far, great information guys, thank you. http://i338.photobucket.com/albums/n420/joe1944usa/223LC86Brittle_002.jpg

Boyd Allen
01-13-2009, 07:50 AM
'Did a little Google on "brass stress cracking ammonia" .

http://www.google.com/search?q=brass+stress+cracking+ammonia&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

I keep my cleaning solvents in a separate box from my brass, just in case.

gerald
01-13-2009, 08:32 AM
M/30, 50/50 with water soak rince and dry.

brian roberts
01-20-2009, 04:56 PM
M/30???

Okay, Larry, I may be all wet, BUT, if you go to Rifle magazine, No.135, Letters To The Editor, there is the original letter. I did NOT get Rifle No. 136 and there was a REPLY to the original in there. I guess I'll have to get that one & read it


243winXB; In your original recipe, you called for a PINT of water. I believe I'd use about two gallons or so. I re-read your original post and thought, that couldn't be right, the vinegar would be too strong & cause problems. I'd use 2-4 gallons, let it sit near the time specified, then dump, put in fresh water & agitate, then dump & fill & let sit 20 mins, then spread out on warm concrete for an hour or two, to dry, mouths pointed downhill.;)

OR, I'd tumble w/ascorbic acid as recommended, & add maybe 1-1.5 oz. of water to the media FIRST(to keep the dust down in a BIG tumbler) then, when the media stopped clumping, & had been running for about 20mins; I'd add the ascorbic evenly, then put in the brass. ;)

243winxb
01-20-2009, 08:09 PM
brian, The vinegar has 15% acetic acid content, so i was thinking thats not a whole lot. But if i read the link correctly, brass will withstand 20% to 100% pure acetic acid. :confused: http://www.hghouston.com/coppers/brass73.htm If i understand this correctly, the rifle brass is strong enough to handle vinegar(acetic acid) for a short period of time (10minutes).:confused:
"Acetic Acid Admiralty brass used for centrifugal pumps handling 20%-100% acid at 20oC"
( Admiralty Brass,copper alloy 260, 70% Copper & 30% zinc used in brass for firearms.) Will Handle Vinegar (Acetic Acid) with no problems. I feel that the NRA RECIPE 1 pint water, 1 cup white vinegar, 1 tablespoon salt, 1 tea spoon detergent will NOT hurt brass when washed for 10 minutes then rinsed for 10 minutes in mild ascorbic acid and sun dried.:confused: There is some arsenic and tin in brass if internet info is correct. :confused:
M/30 http://www.m30.com/

brian roberts
01-21-2009, 03:46 PM
who uses a recipe similar to this, I don't know if it is exact or not. Personally, I don't see a need to "de-zinc-ify" brass at all, unless the nra is just trying to stimulate the economy of the brass manufacturers. What I was really interested in was to cut down on the loss of cases that fell victim to stress corrosion cracking. I read the letter to the editor, thought it made sense, since I'd been told a few times, by an engineer, that upon firing the round, that the chemistry involved, coupled w/the dissimilar materials(copper, steel, debris, etc.), that it was akin to "giving the bore a shot of battery acid...". So, my intent was to do anything possible to forestall, if not eliminate, this condition. I get a bit tired of wearing out cases by expanding primer pockets, let alone destroying them by indulging in the sport; & when I saw I had the same described cracking on my babies, I thought, "...I gotta DO something about this, Tonto...":D SEEya.

243winxb
01-22-2009, 08:12 AM
This recipe for a liquid brass cleaner should be safe. I feel that this recipe containing 1 pint water, 1 cup white vinegar, 1 tablespoon salt, 1 tea spoon detergent will not hurt brass when washed for 10 minutes then rinsed for 10 minutes in mild ascorbic acid (juice from 1 lemon to 1qt water) and sun dried. Firearm brass has many names,( Admiralty Brass, Copper alloy 260 or 70% Copper & 30% zinc, with tiny amounts of tin and arsenic. The acetic acid in vinegar will not harm brass alloy of this type. Admiralty brass is used for centrifugal pumps handling 20%-100% acetic acid at 20oC. http://www.hghouston.com/coppers/brass73.htmWe have learned that ammonia, in any form should never come in contact with brass as "stress corrosion" caused by the ammonia will weaken brass and cause it to crack. "Stress corrosion cracking occurs under the simultaneous conditions of tensile stress and the corroding medium. When you cold work the brass by neck expanding or belling, a residual stress remains in the brass. Also, when the case is fired, the diameter expands to fill the chamber and this causes tensile stress due to stretching."
. One question still needs to be answered. Is ammonia formed/created with combustion of smokeless powder? :confused:

Larry Elliott
01-22-2009, 02:06 PM
[QUOTE=brian roberts;477443]M/30???

Okay, Larry, I may be all wet, BUT, if you go to Rifle magazine, No.135, Letters To The Editor, there is the original letter. I did NOT get Rifle No. 136 and there was a REPLY to the original in there. I guess I'll have to get that one & read it


Just got back online today, and I'll dig out RIFLE 135 and 136 ASAP and get back to you.

Larry Elliott
01-26-2009, 12:08 PM
Brian, finally got off my dead tail and dug out RIFLE No's 135 and 136. The letter writer in #135 had experienced neck splits in 5.56/.223 loads he'd stored for ~2 years in cases that had been fired 2-3 times. The letter in #136, apparently a metallurgist said that he used 2% (weight/volume ?) oxalic or citric acid to rinse ammonia from the cases.

He (#136) said that shooters who used ammonia based cleaners in their rifle's bores had experienced this problem from the remaining ammonia attacking the case necks. I can certainly understand how that could happen, especially if the bore wasn't patched out prior to shooting. He also says that ammonia is produced on combustion of smokeless powder, but the quantity would have to be pretty low I'd think.

Citric acid wouldn't attack brass, and should neutralize any bases like ammonia present in or on the brass. I can't say the same for vinegar, and would worry that if it weren't thoroughly rinsed from the cases that it could do as much damage as any ammonia from powder combustion.

brian roberts
01-26-2009, 05:54 PM
mags. out, would you mind checkin' down to #140, just in case anybody else weighs in downstream??? I'll get my friends recipe, it is basically the same, I believe, except he uses some gallons of water. I think the recipe quoted is too concentrated. He tells me he gets perfection every time, never a problem.;)

Larry Elliott
01-26-2009, 08:35 PM
Brian, no problem I'll check 'em out, but won't promise any speed. Maybe later tonight, maybe tomorrow, but someday.... :D

Larry Elliott
01-26-2009, 08:52 PM
Brian, I got after it tonight and looked at all the letters to the editor in RIFLE up to No. 145, but didn't find anything more on the subject. Lots of info on the .458 Lott and other varmint rifles, but nothing on case cleaning or anything remotely related.

J. Valentine
01-27-2009, 03:39 AM
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.

j.higdon
01-27-2009, 09:21 AM
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.

243winxb
01-27-2009, 09:55 AM
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.

J. Valentine
01-27-2009, 09:45 PM
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.

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.

J. Valentine
01-27-2009, 10:06 PM
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.

What is the active ingrediants in M30 cleaner ?

J. Valentine
01-27-2009, 10:09 PM
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.

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?

Larry Elliott
01-27-2009, 10:18 PM
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.

J. Valentine
01-27-2009, 10:34 PM
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.

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) .

DaRealViper
01-28-2009, 03:01 AM
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.

243winxb
02-03-2009, 08:23 AM
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? 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.

brian roberts
02-07-2009, 04:45 PM
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

brian roberts
03-12-2009, 03:58 PM
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.;)

243winxb
03-13-2009, 08:09 AM
Brian, thank you for the update. All good info guys.

Rflshootr
12-25-2009, 01:04 PM
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?

MarkR
12-25-2009, 02:16 PM
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

Larry Elliott
12-25-2009, 03:16 PM
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?

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.

Old Gunner
12-25-2009, 03:53 PM
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.