Brass discoloration

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TSPIRI

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Hi folks I'm kinda new to reloading only started a few months ago. Anyways I cleaned some sized and deprimed cases in the wet tumbler and they came out shiny and squeaky clean. Used joy and a tiny bit of citric acid.

Once I had them rinsed and the stainless pins all separated I popped them in my toaster oven on the lowest setting to dry. They were a big wet after the first 20 minutes so I doubled down and ran the oven for another 25 minutes. When they came out they were good and dry but looked old and kind of orange-red.

What's going on? I've never had this happen before. I've cleaned brass this way before and it stayed totally shiny.

Isn't the citric acid supposed to keep them bright?
 
I had this same thing happen to me before also, the heat and not rinsing enough caused the surface discoloration.

You can wet tumble again or use a vibratory tumbler to remove the surface discoloration.

I just got a new ultrasonic cleaner this week and did the same thing for the second time, the first was wet tumbling. Its the residue Lemi Shine or vinegar and heat that discolours the cases, in the ultrasonic cleaner you do a rinse with baking soda to neutralize the vinegar residue even after rinsing.
 
According to the chemists it's the acid reacting with the zinc in the brass to create the discolouring. Rinse them well.

I've never dried them in an oven or similar. They stay shiny when dried in front of a fan.

Try Dawn vs Joy. Seems a popular choice.
 
I cleaned a load of brass that turned brown like an old tarnished antique, I believe I used too much lemi-shine , so I put some white vinegar in an aluminum pie plate and added the brass by the handfuls, a little swishing around and it changed back to a shiny brass colour before my eyes
 
People will disagree and think I'm an idiot. But I have used all the methods and ended up going back to old school walnut/corn cob tumbling. Ultrasonic cleaner, case dryer, steel pins etc just sit in the corner and do not get used.

Extra time and steps for no reason.

Plus brass that gets squeaky clean inside the neck can increase ES unless you lube when seating bullets.

Dry media tumbling leaves just enough carbon inside the neck to provide a dry lube when seating bullets.
 
I still have my two dry media tumblers along with my wet drum.
Sometimes run all three if in a hurry, but use the wet/ ss pins when I want the primer pockets free of crud.
Hate getting dry media out of the flash holes.
 
The discoloration is from residual citric acid left on the case plus the heat from the toaster overn. I had this problem too when I first started wet tumbling. I use a 9mm case of lemishine and a big squirt of dawn dish soap. I also rinse the brass for 5 minutes in a media separator with hot running water then rinse directly under the tap with water as hot as I can tolerate. I then shake them out in the media separator basket and dump into a bath towel and shake vigorously in the towel to get the outside of the case dry-ish. Then into the dehydrator to dry the inside.

Doing it this way keeps my brass from discoloring over time. If I skimp on the rinse they still get a little tarnished. That's due to residual citric acid. Gotta get the lemi shine off completely.
 
Longboat said:
People will disagree and think I'm an idiot. But I have used all the methods and ended up going back to old school walnut/corn cob tumbling. Ultrasonic cleaner, case dryer, steel pins etc just sit in the corner and do not get used.

Extra time and steps for no reason.

Plus brass that gets squeaky clean inside the neck can increase ES unless you lube when seating bullets.

Dry media tumbling leaves just enough carbon inside the neck to provide a dry lube when seating bullets.
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I find that I'm using my vibratory tumbler more than my STM wet tumblet because wet tumbling peens the case mouths. And then I have to trim the cases every time I wet tumble and then deburr the cases.

This week I got a ultrasonic cleaner and experimented using dish washing liquid, Lemi Shine or vinegar and got chemical discoloration when using heat to dry the cases. I think the problem was not rinsing long enough and not submerging the cases. In a YouTube video using a ultrasonic cleaner and vinegar, baking soda was used in a rinse cycle to neutralize the vinegar.

I do not think there is a perfect cleaning method that doesn't take extra time and effort. It takes 20 to 30 minutes for a ultrasonic cleaner to warm up the water for proper cleaning. And it still takes several cleaning cycles to get the primer pockets clean.

Bottom line, I think its high heat temp that causes the discoloration on the cases.
 
bigedp51 said:
I find that I'm using my vibratory tumbler more than my STM wet tumblet because wet tumbling peens the case mouths. And then I have to trim the cases every time I wet tumble and then deburr the cases.

This week I got a ultrasonic cleaner and experimented using dish washing liquid, Lemi Shine or vinegar and got chemical discoloration when using heat to dry the cases. I think the problem was not rinsing long enough and not submerging the cases. In a YouTube video using a ultrasonic cleaner and vinegar, baking soda was used in a rinse cycle to neutralize the vinegar.

I do not think there is a perfect cleaning method that doesn't take extra time and effort. It takes 20 to 30 minutes for a ultrasonic cleaner to warm up the water for proper cleaning. And it still takes several cleaning cycles to get the primer pockets clean.

Bottom line, I think its high heat temp that causes the discoloration on the cases.
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It might just be me being lucky but the amount my case mouths get peened over is just the right amount that needs to be trimmed off and just chamfering the mouth keeps all my cases at min trim length. This has been working for me for 6 reloads on 308 6.5cm and 7mm08 so far. I think it's just pure luck on my part. But whatever it is its sure handy.
 
bigedp51 said:
I find that I'm using my vibratory tumbler more than my STM wet tumblet because wet tumbling peens the case mouths. And then I have to trim the cases every time I wet tumble and then deburr the cases.

This week I got a ultrasonic cleaner and experimented using dish washing liquid, Lemi Shine or vinegar and got chemical discoloration when using heat to dry the cases. I think the problem was not rinsing long enough and not submerging the cases. In a YouTube video using a ultrasonic cleaner and vinegar, baking soda was used in a rinse cycle to neutralize the vinegar.

I do not think there is a perfect cleaning method that doesn't take extra time and effort. It takes 20 to 30 minutes for a ultrasonic cleaner to warm up the water for proper cleaning. And it still takes several cleaning cycles to get the primer pockets clean.

Bottom line, I think its high heat temp that causes the discoloration on the cases.
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It is not recommended to clean brass in a warm or heated solution. That will definitely discolor it. Only gun parts should be cleaned in a heated solution.

Aside from all the chemical reactions causing discoloration, if you rinse your cases with anything other than distilled or RO water you are going to have water marks on your cases. Especially if dried with heat.

As was mentioned dry media does get stuck in flash holes. But it takes only 5 min to poke a toothpick through 200 cases to clear them.

I found sonic cleaning to be much more of a pain in the ass personally. And does absolutely nothing in the very least for accuracy. If anything it can decrease accuracy and increase ES and SD from what I have seen on Lab Radar and vertical dispersion 500-1000 yards.

Steel pins are great. It has been lab proven that steel pins harden the very outside layer of the brass, although that seems to be a non issue you would never notice. I should note the main reason I do not use steel pins is I anneal with an AMP induction coil annealer. And do not want to risk a wedged in steel pin making it's way into the machine.
 
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Longboat said:
It is not recommended to clean brass in a warm or heated solution. That will definitely discolor it. .
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The instructions for cleaning brass cartridge cases with my sonic cleaner tells me to preheat the cleaning solution to aid cleaning. It also states to use hot water to speed up the warm up time.

I can tell you dumping 50 .357 cases in the sonic cleaner using cold tap water and no warm up did not clean the cases. I then took the time to totally read the Chinese instructions and making sure the cleaner was up to temp. And it can still take four eight minute cleaning cycles to get the brass reasonably clean.

No More Dirty Brass — How to Use Ultrasonic Cleaning Machines
http://bulletin.accurateshooter.com/2016/10/no-more-dirty-brass-how-to-use-ultrasonic-cleaning-machines/

Cleaning Brass with the RCBS Ultrasonic Cleaner
https://ultimatereloader.com/2015/08/12/cleaning-brass-with-the-rcbs-ultrasonic-cleaner/

"Here’s a breakdown of the process:

Drain and clean ultrasonic cleaner (I saved the solution I cleaned dies in because it was still rather clean)
Fill the ultrasonic cleaner with solution (I just pour in water and solution and mix in the stainless tub)
Turn on the ultrasonic cleaner, activate the heater, wait for it to come up to temperature
Set the appropriate time interval for your cleaning (I used 30 minutes)
Activate the cleaning cycle
Wait until cleaning cycle is done
Lift out basket, lightly shake/tip to remove excess solution
Dry cases (I put them in a tub in the sun, you can also use your oven at low temp)"

NOTE, again I get the discoloration during drying the cases too long at high temps. Air drying at room temp does not cause the discoloration.
 
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Interesting. Hornady says the opposite and recommends no heat. They say heat will discolor the brass. But that's with their solution.

One thing that is for sure, heat speeds up chemistry drastically.

Whatever works for the individual. I tried those methods and was not impressed and took even longer to do. If it works for you and you like it I'm not going to say dont do it or my way is better.
 
Usually spread them out on a bunch of cheap towels near the wood stove or outside in the sun depending on the weather and roll them around now and then.

Did three full loads on a FA wet tumbler of 9mm including numerous range finds all came out nice and clear brass.

Probably lucked out with the cleaning solution mixture of usual joy and lemi. Maybe the towels and movement may have wiped them before it dried out on them as well.
 
Longboat said:
Interesting. Hornady says the opposite and recommends no heat. They say heat will discolor the brass. But that's with their solution.

One thing that is for sure, heat speeds up chemistry drastically.

Whatever works for the individual. I tried those methods and was not impressed and took even longer to do. If it works for you and you like it I'm not going to say dont do it or my way is better.
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The first time I used the ultrasonic cleaner I used dish soap and Lemi-Shine but the water never reached the desired temp. And these cases did not change color when dried, using a 5 gallon plastic bucket and a hair drier. The second time I used vinegar, salt and dish soap with hot water and dried the cases the same way and these cases changed color.

That being said the first time my cases changed color was after wet tumbling and again drying in a bucket with a hair drier. My conclusion was the high heat and drying time caused the discoloration. This was a large batch of .223 cases and only the top cases in the bucket changed color and the bottom cases in the bucket looked normal. And this was just dish soap, Lemi-Shine tumble. And tumbling again wet or dry will remove the surface discoloration.

Homemade Firearm Cleaners & Lubricants
https://www.frfrogspad.com/homemade.htm

Chemical Case Cleaning Solutions

While tumbling cases in an abrasive media provides the best finish, extremely dirty cases can be decapped first (using a non-sizing die) and then washed in one of the following solutions. The final rinse in soapy water helps prevent tarnishing. All of these methods were approved by Frankford Arsenal and will not weaken your brass.

A 5 percent solution of citric acid (available from your drugstore) and warm water for about 10 minutes. If your water is very hard increase the amount of citric acid. You can add some Dawn™ or Cascade™ dishwasher liquid soap (which does not contain ammonia--be careful some do), 409, or Awsome to the solution for extra grease cutting ability. Follow with a rinse in hot soapy water (Ivory™ works well) and allow to dry. Don't overuse the citric acid or the brass may discolor.

A solution of 1 quart of white vinegar and 2 tablespoons of salt. Soak with some agitation for 15 to 20 minutes and follow with a rinse of soapy hot water and allow to dry.

A solution of 1 quart of water, 1 cup white vinegar, 1/2 cup lemon juice, 1/4 cup laundry or dishwashing detergent, 1/8 cup salt. Soak with some agitation for 15 to 20 minutes and follow with a rinse of soapy hot water and allow to dry. This may leave brass with a slight pinkish cast which will disappear with a short tumble in media.

Military arsenals use a heated 4 percent sulfuric acid dip with a little potassium dichromate added. The solution is heated until bubbles rise slowly without it boiling and the cases are dipped into it for 4 -5 minutes using a basket of copper screening or plastic. A final rinse using plain hot water is followed by hot water with Ivory™ soap in it and the cases are left to drain and dry. Because of the use of heated sulfuric acid this method is probably impractical for home use but is given here to show what can be safely used.

Cases which have been fired several times and which show signs of carbon build up internally can be rinsed in straight paint & varnish makers (P&VM) naphtha available at any paint store. Decap, soak for 5 - 10 minutes, drain, allow to air dry and then tumble as usual. Cases will be sparkling clean inside and out but not any shinier.

An interesting idea is to use an "air stone" and a small air pump from a fish aquarium tank to agitate the liquid cleaning solutions.

Thanks to Randy Wood for this tip.

Another case cleaning method is the use of an ultrasonic cleaning unit. These units are available from several online sources and the biggest problem is finding a reasonably priced unit with about a 2 liter capacity. While you can only clean small quantities of cases at a time this way they will be clean as new, inside and out. Once you've acquired the unit you'll need to also acquire a glass beaker of sufficient size for your use and make a cover and beaker holder.
 
I have to agree with the guys who pointed to over use of acids resulting in that brown discoloring. Brass is a mixture of copper and zinc and when you are using acid you will dissolve the zinc and leave behind the copper color. That is why you see the copper color = orange/brown. Copper is from the same family as gold and silver and those are all more resistant/inert to being dissolved by the acids.

I get incredible results in the following way.

Fill the tumber 2/3 or less with cases. Add in 5-6 pounds of stainless steel tumbling media. You can buy more medial off places like amazon.ca but I find I can get better prices off amazon.com even with the US dollar exchange. Buy the 0.047" media which I find gets stuck less often in the brass and needs less inspection after drying.

I then fill with hot water to the 3/4 or more level. Make sure you leave a good amount of air in the tumbler or you will need to tumble for a longer period of time. Water slows the fall of the brass and media in the tumbler and slows the overall cleaning of the brass. I then add half a teaspoon of citric acid or a couple teaspoons of high concentrate vinegar I buy from any cleaning store, home hardware, or other reno store. You can use any vinegar for this but adjust the amount to the concentration of acetic acid. Regular white vinegar is 3-4% acid. Pickling/canning is 5-7% acid. Cleaning acid is 10-25% acid. Over use of acid will cause discoloration. I then add 1 teaspoon of Nellies laundry soda https://www.costco.ca/Nellie’s-Bulk-Laundry-Soda-.product.10334416.html.

I then tumble for 1.5 - 2 hours which is all I find necessary. When I am finished tumbling, I immediately drop the brass and solution into a large sink, barrel etc. I drain the solution away swirling the brass and wash it in water again. While I am washing I tumble the brass in the sink so any solution left behind inside the brass gets washed away. Once the brass has been washed (10 minutes max), I drain the water, tumbling it again by hand to just take away the rest of the water. I then tend to let it air dry over night.

That results in brass that is brighter than I get from store bought ammo. I will try to post some pictures later on.

If anyone in the Alberta area wants any of the dry solution additive, send me a message and we can arrange for you to get enough to do a brass cleaning run. My 5 gallon pail of Nellies laundry soda will take a life time to use up even though I have washed at least 15,000 casings so far. It has barely dented the pail. On the bright side it is almost better than regular liquid laundry soap and I use it for clothes as well. I don't mind giving a small amount away if anyone local wants to try it. heck I will ship anywhere if you pay the shipping.
 
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