Pink hue after media tumble.

[brokeasajoke]

My 44spl Starline brass came out nice but my Federal and others came out like this. Starline
left and a Rem on right. Seems like that's something about zinc maybe. Pic doesn't really do justice to color difference. This was some pretty old corn cob media with nufinish.

I know it's fine but was just an interesting observation that all brands but Starline was discolored.

 

[Twicepop]

I've seem this before, my best guess is that it is a slight chemical reaction with the copper in the brass. The ones I had that did this, after a second tumble the "pinkish" color really diminished or went away completely.

 

[JMayo]

I use to wash my pistol brass in Vinegar, water, salt . Too much Vinegar turns brass pink

 

[NZ_Fclass]

Did you leave a red sock in the tumbler?

 

[snert]

I too have had this happen, with wet wash too long in citric acid. It didn't make a lick of difference. I just gave them to my daughter. Last week we were shooting 400 yard steel and I hit one low. It spun on edge. It was half inch plate. She proceeded to knock it over, 400 yard hit on edge of 1/2 inch plate. I think pink rules.

 

[piie]

Just your brass coming out...

Different solvents with different brass will cause this to lesser/worse extent - mostly dependent on the specific composition of the brass alloy. Superficial - Brasso or some other non amonia containing cleaner will restore the yellow colour.

 

[Oso]

As indicated to much acid - too much Lemishine.

With .223/5.56 there are a few manufacturers of brass whose alloy composition always results in a "rose hue" after wet tumbling while every other headstamp in the batch comes out white gold perfection. There is no difference in performance.

Que Serra Serra ... breaking up the monotony of tumbling brass!

 

[EOD Rob]

As indicated to much acid - too much Lemishine.

With .223/5.56 there are a few manufacturers of brass whose alloy composition always results in a "rose hue" after wet tumbling while every other headstamp in the batch comes out white gold perfection. There is no difference in performance.

Que Serra Serra ... breaking up the monotony of tumbling brass!

Yep, to much lemishine will cause this. Took me a few times to learn this what I first started using it. Doesnt cause any reloading of firing issues, just look weird.

 

[Ned Ludd]

As other have noted, too much Lemishine. With Lemishine, a little goes a long way. The citric acid is a negatively-charged chelating agent that binds and sequesters positively charged metal ions, especially divalent metal ions, from the surface of the brass alloy. The color may also be part of a redox reaction due to the acidity when too much Lemishine is used. Because the brass is an alloy, the Lemishine will not chelate or oxidize metal ions other than at a very, very thin layer (think about one or two molecules deep) that are exposed at the surface of the metal, so the pink color does not mean that metal ions have have been leached out of the interior of the brass or that the brass is ruined. In fact, after the pink brass is fired, then cleaned using a more appropriate amount of Lemishine, the normal color will return.

 

[D-4297]

^^^^ What he said . I've gotten some pink brass , but only on the necks . I continued to process it . After sizing , and during the second "wash" , using less Lemmi-shine , the normal brass color came back . But the Pink necks were kind of cool .

 

[Shooter13]

Lemishine will do this too!

 

[Dub]

I thought he said media tumbled?

 

[Oso]

I thought he said media tumbled?

SHhhh - I sound like I know something. No one said there was a pop quiz on reading comprehension!

 

[TMc]

Well I was going to ask a similar question about 9mm range brass I pick up. I wash with citric acid/salt/dawn/hot water and shake around in old apple sauce jar. If I leave them in to long, over 30 min, they get a pink hue. this thread seems to indicate good to go. Thanks all!

 

[Doom]

To clarify what is happening the most likely cause is exposure to acidic compounds that remove the zinc on the surface leaving only copper.