Is it okay to shoot "pink" brass?

[razorfish]

I've noticed that some my range pickup brass comes has a dramatic "pink" cast to it when exposed to a 4:1 solution of vinegar (acidic) and water with soap added.

Brass is an alloy of Copper and Zinc. From what I understand, some cases, especially when submerged in water for a period of time leach/lose zinc from the brass. After the brass is polished it has pink cast to it and looks more like copper than brass.

I generally discard any brass with these symptoms, but I'm wondering if I'm just throwing away safe, useable brass.

What say the experts...

[B_Seehawer]

I think you are looking into it a little too far.

Run a good magnet (or toss one in your tumbler) over it, pick out the steel cases stuff and pitch it.

[MarkCO]

I would not shoot it. It is called dezincification and when you can visibly see it, you have lost a good amount of strength. As a forensic engineer, have seen this many times, not often pretty.

[razorfish]

I think you are looking into it a little too far.

Run a good magnet (or toss one in your tumbler) over it, pick out the steel cases stuff and pitch it.

I suppose I could be over analyzing it, but we're talking pink here...

First Two Cases, just washed.

Middle Case, washed then polished with nut.

Last Two Cases, normally processed/cleaned brass

[TonyK]

I'm with MarkCO

Nor am I a fan of picking up someone else's stray brass, you have no idea what it has been through and you can be sure in that shape it has been laying on the ground for awhile.

All it takes is one to blow out and ruin your day, maybe your gun or your hand....

[Shadowrider]

Long time ago I tried Birchwood Casey liquid brass cleaner. IIRC it's a phosphoric acid or maybe citric. I mixed it with water and cleaned following the instructions to the letter. Result = clean shiny pink brass. They didn't look the same as yours but they were pink as heck. I didn't have any issues with the brass but I neutralized it and dumped the solution. I figured what was happening couldn't be good. You are probably OK cleaning once with it, but I certainly wouldn't clean with it as a normal regimen.

[razorfish]

Long time ago I tried Birchwood Casey liquid brass cleaner. IIRC it's a phosphoric acid or maybe citric. I mixed it with water and cleaned following the instructions to the letter. Result = clean shiny pink brass. They didn't look the same as yours but they were pink as heck. I didn't have any issues with the brass but I neutralized it and dumped the solution. I figured what was happening couldn't be good. You are probably OK cleaning once with it, but I certainly wouldn't clean with it as a normal regimen.

I think the acid in these solutions (lemishine, Birchwood Casey or Vinegar) causes the dezincification to become obvious (ie. the bright pink hue before polishing). I am just finishing up cleaning 4000 9mm cases of one-shot range pickup brass. Out of 4000 I had about 20 become obviously pink as in the pictures above and another 20 with pink areas on them.

In other words, using a mildly acidic solution removes any tarnish from the brass but also appears to expose any brass that is a "little low on zinc".

I guess at this point I will continue to discard them. I'm guessing the zinc makes the copper "harder" or "tougher" so less zinc could mean weaker cases.

On the other hand before I used the vinegar solution to wash my brass I rarely noticed the pink/copper looking cases. Maybe these cases are just fine to load or maybe I was just lucky.

[Shadowrider]

Basically yes everything you said is correct. The zinc adds strength to the copper and it's throughout the matrix so I doubt removing a small amount on the surface only is going to have any real effect in the grand scheme of things. Now if we were to "acid wash" them before each loading, that would be a whole different matter. If you are leaving them in a pretty weak solution, and since you are using vinegar it is, and for only a few minutes (like 10 minutes max) and rinsing them really well, I can't see any real danger. It might be a decent way to "spritz up" pretty heavily oxidized range brass but I'd prefer the wet stainless tumbling method with just plain old soap. It's actually more effective with the mechanical action of the pins.

[razorfish]

If you are leaving them in a pretty weak solution, and since you are using vinegar it is, and for only a few minutes (like 10 minutes max) and rinsing them really well, I can't see any real danger. It might be a decent way to "spritz up" pretty heavily oxidized range brass but I'd prefer the wet stainless tumbling method with just plain old soap. It's actually more effective with the mechanical action of the pins.

I notice that many people using stainless media add Lemi Shine to the water. Lemi Shine, Vinegar and many commercially available brass case cleaning solutions are all weak acids.

You can substitute a 45 case full of Lemi Shine for a cup of vinegar using my cleaning process and get the same results. So not only is Lemi Shine acidic, but I would say it's a pretty powerful acid (citric acid) based on the idea it only takes a "dash" of it.

There's another reloading group on Facebook (an offshoot of Powder Valley) that calls the technique L.S.D.. They prescribe using LemiShine in place of the Vinegar and Salt to clean cases. Of course you need the detergent (Dawn) but no tumbler. Just a quick stir and magically you have shiny brass (and a few pink ones).

Do you continue to use LemiShine when you clean cases in the tumbler for a second time?

[MarkCO]

These topics amaze me. Someone wants to put an aftermarket connector in their Glock and a bunch of people scream about how bad an idea it is, when there is absolutely NO evidence to support that contention. Then someone asks about discoloration on brass, which is obviously dizincification, and a bunch of people say it is fine, even though they have no idea what they are talking about.

Razorfish, I gave you an answer based on solid evidence and my professional work as a forensic engineer. If you would like more info, send me a PM. Signing out on this thread.

[razorfish]

Razorfish, I gave you an answer based on solid evidence and my professional work as a forensic engineer. If you would like more info, send me a PM. Signing out on this thread.

Advice was heard loud and clear... I toss any case that has these symptoms.

BUT you have failed to note that the thread changed directions...

Now we discussing whether an acid based cleaning solution could be causing and or aggravating the issue. (Acid based solutions... Vinegar, LemiShine, Birchwood Case Cleaner, etc.)

I don't think this is the case and continue to clean my cases using vinegar. (I like shiny brass and besides it helps me to quickly identify any cases that are "low on zinc")

So with your skills as a forensic engineer, does a quick dip in LemiShine (citric acid) or Vinegar do any harm to the brass? I'm sure the stainless pins/tumbler/lemishine guys would want to know the answer.

[MarkCO]

So with your skills as a forensic engineer, does a quick dip in LemiShine (citric acid) or Vinegar do any harm to the brass? I'm sure the stainless pins/tumbler/lemishine guys would want to know the answer.

I noticed. Yes, it can. No, they did not want to know. In fact some of my posts that had proof and photos are no longer in the thread on the topic.

[razorfish]

I noticed. Yes, it can. No, they did not want to know. In fact some of my posts that had proof and photos are no longer in the thread on the topic.

Thanks... good info to know.

I know something is being removed from the casings. As an experiment you can take some clean steel nuts and bolts and toss them in the used brass cleaner. Leave it overnight and they look like they've been electroplated with copper.

Based on this advice I will certainly limit my use of acidic cleaning solutions. I would say I would entirely stop using these solutions, but I really like shiny brass... besides I never said I was all that smart (Guys like me ensure job security for forensic engineers, but I will definitely be more careful moving forward)

[Sarge]

I love shiny brass as well. But a couple of hours in walnut and a few more in corn cob makes my brass extremely shiny! Washing brass is a PITA as you have to lay it out to dry which depending on the season can take a long long time.

The only time I ever wash brass is if I pick up a bucket full from working a major match in a very sandy area. Then, all I do is just slosh it around in a bucket of soapy water for a few minutes, rinse, and lay it out in the sun.

I have seen and heard enough from knowledgeable folks, such as MarkCo, on the matter to believe it is inadvisable to wash brass as part of a routine.

Edited December 8, 2013 by Sarge

[TonyK]

If you want a dramatic example of why not to expose brass to chemicals, put some cases in a jar that will expose them to ammonia fumes...

I use this technique to intentionally corrode and color brass hardware on furniture I make.

Any brass that has been stressed during manufacturing will crack. And as you may know our cases are all "stressed" when they are made.

[RDA]

Any brass that has been stressed during manufacturing will crack. And as you may know our cases are all "stressed" when they are made.

I believe they are also "stressed" when they are used as intended.

Edited December 8, 2013 by RDA

[21 shooter]

I would like to use the steel pin tumbling method but having to deprime first is an extra step in the process. An engineer friend of mine told me the same thing MarkCO stated. Many years ago I tried a formula for water, citric acid and something else. I wound up adding those cases to the scrap bucket.

I have read very little about trying nothing but Dawn other than the cases might not be as shiny. I think wet tumbling has possibilities but different additives are needed. Just my .02 worth.

[Shadowrider]

Dang Mark, a little harsh?

Since we're comparing, a little of my background. Former division manager responsible for chemical processing, non-destructive testing, coating and finishing of precision aerospace components made from aluminum, stainless steels, carbon steels and titanium and occasionally non-ferrous metals and plastics. This included the most stress critical and fracture critical stuff like engine mounts, landing gear and also parts in sonic areas. (around the engine when subjected to extreme heat AND cold AND in the area of a supersonic wave, really strange unexplainable things happen)

Pretty much anything structural in a missile or aircraft, also some damn cool gun systems, M230E1 receivers are an over toleranced nightmare but that's another thread somewhere else.

Among many other duties I was responsible for monitoring tank solutions and process compliance to our customer's specifications. Many of the coatings we applied can only be validated by weighing the coating applied. They are just too thin to measure and receive any tangible result. This was done by weighing a sample, etching the coating off and weighing again, then doing a little math to arrive at a coating weight per square inch. We had a full blown lab to do all of this.

Our customers included Lockheed, Northrop, Raytheon, Boeing, Bombardier, Cessna, Bell Helicopter, Gulfstream, and on and on. I've worked on and built parts for just about everything in the air today from the F-16, F-18, F-22 all the way to C-130 and C-17s and even missile defense. Prior to that I was as machinist, CNC programmer, and manufacturing engineer building these same parts. Yes I do know a bit about metals.

Wet tumbling is fine, but when I posted "plain old soap" in my post above? Yea, that was addressing the acid based cleaning solution. You see soap like Ivory and the like is alkaline.

Edit: I went a bit over the top. The key is to be reasonable on the amount of any cleaner and the duration you leave your brass in. And also what's in your water.

Edited December 9, 2013 by Shadowrider

[MarkCO]

I answered your question in a PM.

[MarkCO]

Guys like me ensure job security for forensic engineers, but I will definitely be more careful moving forward

Trust me, you would not want me to be involved with you in a professional capacity. It would mean you are hurt or hurt someone else, either physically or financially. Knowledge and caution will help keep the vast majority of people safe, but there is nothing I can do about left hand turns.

[Shadowrider]

MarkCO and I had a quite good PM discussion and we are good, so those wanting internet drama will have to keep looking.

Bottom line is we're both correct. Just be informed of whatever chemicals you let touch your brass. If you buy a prepared mixture, follow the instructions to the letter and use deionized (best) or distilled water to mix it up and don't use the oven to dry.

[grapemeister]

Sprinkle in some baking soda next time and that'll take care of the problem. My mixture (The Magic Formula, formerly known as the secret formula) is two cups water, 1/2 cup lemon juice, 1 cup vinegar, and then I sprinkle in just enough baking soda to create a good fizz. The baking soda nuetralizes the acid just enough to keep the zinc from leaching out and causing the pink color. I also put in a few good squirts of dish soap. I use a toilet bowl brush to swish around, and scrub the brass.

I let the brass soak for about 30 minutes, rinse them in a metal spagetti strainer, and spread them out on a towel to dry. After they dry, it's in the tumbler for several hours with a mixture of corn cob media, Nufinish, and a little Cabela's case polish.

The magic formula doesn't shorten the life of the brass for relaoding. I use the magic formula to clean all my brass, some of which has been loaded 10-12 times.

I would discard the pink cases. If your getting pink that means a lot of zinc has leached out which leads to brittle brass.

Oh, by the way, there is absolutely nothing wrong with range brass. Use good since, inspect the brass, and the load the hell out of it.

Correction: 1/2 cup lemon juice, not 1/4 cup.

Edited December 9, 2013 by grapemeister

[Kraj]

With brass being free as far as im concerned I just toss it. It probably fine, but your risking what for .06?

[Steve RA]

Some of the "pink" ones come from having laid in acidic soil for an extended time. If they are noticeably pink I personally put them in the scrap brass bucket. Then you will occasionally come across ones that are pure black, I've got a 9mm Win case that I ran through the stainless process twice, tumbled for a total of 4 hours in walnut and is still all black. It's very shiny, perfectly clean in the primer hole, inside gleams but is extremely shiny.

I'd be interested to hear any theories on what turns the rare case black ???

[grapemeister]

Some of the "pink" ones come from having laid in acidic soil for an extended time. If they are noticeably pink I personally put them in the scrap brass bucket. Then you will occasionally come across ones that are pure black, I've got a 9mm Win case that I ran through the stainless process twice, tumbled for a total of 4 hours in walnut and is still all black. It's very shiny, perfectly clean in the primer hole, inside gleams but is extremely shiny.

I'd be interested to hear any theories on what turns the rare case black ???

I think it's just from being in the elements too long. The climate and soiI may have something to do with it. I do all my shooting here in Florida and pick up range brass anytime I have a chance, including the black ones. It seems like I find more black cases in different parts of the state than I do others. But, is it becuase of the difference in the climate and soil, or is it because the cases have just been on the gound longer....who knows. I do know that if the cases have been buried, it certainly speeds up the cases turning black. I suspect that most of the ones I find were buried at one time, and the rain along with foot traffic have uncovered them.

I load them either way, but the black ones I usually just use for practice ammo.

Edited December 26, 2013 by grapemeister