Black residue on brass, need help!

[satou]

So the other day a friend of mine gave me bucket loads of military brass that was just covered all over in this black stuff and what looks to be calcium build up or something or other. Well the brass didnt look so bad, so I went ahead and tumbled a load in some unused dry walnut media. After leaving it overnight i was left with brass that had this black discoloration and I am not sure as to what it is, and how to get it off.



If been doing a little research on my own to use things like a very mild mixture of vinegar or use windex to remove this discoloration. But i wanted to get some more information before i go ahead with any other steps to remove this black crap that is on all the cases.

[OldShooter32]

Brass

You need some Lemishine and stainless pins to really kick that crud. I've done a BUNCH of GI brass that bad and 45 minutes in water, Lemishine and detergent, along with some SS pins will make them shine.

Decap first, then tumble -- the pockets will be clean and the water will drain better. Dry them in the sun or on a sweater rack in the dryer.

They will have a burnish and will be clean. Size them, then run them in walnut with some NuFinish to take off the lube and they will have a great mellow shine on them. Better on the rifle and much easier to find in the grass if you shoot a gas gun.

[the86d]

It looks like major oxidation. Walnut media isn't treated with anything, is it?

Odorless Mineral Spirits tumbled with cob might cure this?

I don't use walnut (my lady is allergic), only cob, and mineral spirits with some Brasso.
(Research: "over 25 years" @ http://www.thehighroad.org/archive/i.../t-255902.html if going to talk Brasso-smack. )

[satou]

You need some Lemishine and stainless pins to really kick that crud. I've done a BUNCH of GI brass that bad and 45 minutes in water, Lemishine and detergent, along with some SS pins will make them shine....

Thanks i might have to buy some ss medial, It also seems i may have to get a more heavy duty tumbler to use the stainless steel media if i am not wrong? As in a vibration tumbler probably wont make the cut.

Excuse me for having asked quite a few questions, just never came across brass that looks like this. Only about 6 months into reloading.

It looks like major oxidation. Walnut media isn't treated with anything, is it?

Odorless Mineral Spirits tumbled with cob might cure this?

I don't use walnut (my lady is allergic), only cob, and mineral spirits with some Brasso.
(Research: "over 25 years" @ http://www.thehighroad.org/archive/i.../t-255902.html if going to talk Brasso-smack. )

No the walnut media was not treated with anything, the brass more or less looks like this with some extremely dirty:

[OldShooter32]

Water damage, maybe brass picked up on a range after the grass was burned...lots of reasons.
I use a $100 (ok, now $150 i see) small cement mixer from Harbor Freight...it's running right now with 500 or so .308 cases.

http://www.harborfreight.com/1-1-4-quarter-cubic-ft-compact-cement-mixer-91907.html

If you're near me, bring it by and we'll run it through mine. (Lodi/Stockton area)

[the86d]

No the walnut media was not treated with anything, the brass more or less looks like this with some extremely dirty:...

I have gotten some really old, oxidized/tarnished brass from under wooden walls at my range... none THAT bad, though.

Brasso, odorless mineral spirits, and some cob resolved all the issues I have dealt with, but yours seem to be more...
intense.

I would give Mineral Spirits and Brasso (or tumbling polish?) with some cob a try...

[satou]

Water damage, maybe brass picked up on a range after the grass was burned...lots of reasons.
I use a $100 (ok, now $150 i see) small cement mixer from Harbor Freight...it's running right now with 500 or so .308 cases.

http://www.harborfreight.com/1-1-4-quarter-cubic-ft-compact-cement-mixer-91907.html

If you're near me, bring it by and we'll run it through mine. (Lodi/Stockton area)

Eh, yea i figured it was water damage since it looks like calcium build-up on some of the cases. Looks like I might have to upgrade my current set-up for cleaning brass now.

I would gladly come on by and learn from a more experienced person, alas ventura is a good 5 hrs from stockton.

Thanks for the great information by the way, gonna have to figure out a way to convince the family i need a new tumbler.

[OldShooter32]

If you use walnut media, add a capful of NuFinish car polish and a half a dryer sheet (cuts the dust) -- put it in about ten minutes before you add brass so it can distribute across the media.
It won't cut through this degree of crud in a reasonable time, but for "normal" brass, it will make it look as good as any of the expensive cleaners. The media I sell is untreated, so this is a trick I've learned.

[satou]

I have gotten some really old, oxidized/tarnished brass from under wooden walls at my range... none THAT bad, though.

Brasso, odorless mineral spirits, and some cob resolved all the issues I have dealt with, but yours seem to be more...
intense.

I would give Mineral Spirits and Brasso (or tumbling polish?) with some cob a try...

Yea i know, this small batch is just about what all of the brass my bud gave me looks like. I may give your suggestion a try will probably head over to wally world today to pick up some brasso.

On a side note, though probably not recommended but just had to ask. Is it okay to load these? Just merely asking wont actually do it.

[OldShooter32]

Good luck! The best part is that I can use my brass tumbler to mix cement when I set fence posts!
Try THAT with your Dillon!
(I use a vibratory tumbler with the walnut though...so I ain't completely crazy.)

Check the cases after you get them clean. See if there are cracks, pits, etc. and chuck those in the scrap bin. If the cases look intact, load them light (as should be the normal practice) and try them out. GI cases are generally extra thick compared to civilian brass, so they should be ok. Can't really tell without seeing them tho.

[satou]

Good luck! The best part is that I can use my brass tumbler to mix cement when I set fence posts!
Try THAT with your Dillon!
(I use a vibratory tumbler with the walnut though...so I ain't completely crazy.)

Haha thanks, its funny that you mention cement mixing. My old man always taught me to do things the way that make you sweat and sore, in a sense just plain old being a man. So we always mixed cement by hand in an old wheelbarrow and have never done it any other way.

I may have to cheat and buy that rotary mixer though, would make a lot of things around the house much easier.

By load them, i mean in their current state. With all that crud on em ala my first post. Bear in mind im not going to go ahead and do this was just curious is all.

I know mil brass is generally much more better suited to reloading more often than regular brass. And i always check my brass for any cracks or fractures.

[asm_]

You can probably clean that up with overnight soak in vinegar. However, I wouldn't use them for reload. Vinegar "cleans" the brass by leaching away zinc. Standard case have 70% copper 30% zinc. Reducing the zinc level may become a safety issue.

B

[Socalman]

I am not a metallurgist but brass is an alloy. After time untreated (coated with lacquer) brass will begin to go through a process similar to oxidation. It is something I see quite often with brass musical instruments. I would certainly not load those cases anywhere near to full power. I would stay on the lowest possible pressure side.

[pisarski]

just soke them in vinegar and water for 2 to 3 hours them tumble with walnut will look like new in no time