Pinkish spots on brass after annealing

JRBullock1987

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Every time I anneal I get a couple pieces of brass that get a pinkish blotch on the annealing area. The flame Hotspot (blue part) isnt directly touching the brass. I always have the brass annealing until the flame starts warming (changing color) exactly how your supposed to anneal. Does this make that piece of brass unusable or give it a weak spot? What causes it? It would make sense if I was blasting the brass really close but im anneal exactly how youre supposed to anneal with an open flame.
 

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Without having that in a lab it is hard to say what caused the spot.

It could be something that was on the brass during the anneal, or it could be "in" the brass.

My guess, is that it is cosmetic and shouldn't matter.

If you are still worried, scrub it and that will help show if it is just superficial or deep.
 
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Every time I anneal I get a couple pieces of brass that get a pinkish blotch on the annealing area. The flame Hotspot (blue part) isnt directly touching the brass. I always have the brass annealing until the flame starts warming (changing color) exactly how your supposed to anneal. Does this make that piece of brass unusable or give it a weak spot? What causes it? It would make sense if I was blasting the brass really close but im anneal exactly how youre supposed to anneal with an open flame.

What is your cleaning process?
 
Without having that in a lab it is hard to say what caused the spot.

It could be something that was on the brass during the anneal, or it could be "in" the brass.

My guess, is that it is cosmetic and shouldn't matter.

If you are still worried, scrub it and that will help show if it is just superficial or deep.
Good thinking. Thanks
What is your cleaning process?
I use a 50/50 treat corn cob/ reg corn cob mix.
 
I use a 50/50 treat corn cob/ reg corn cob mix.

The reason I asked was to see if you're wet cleaning (ultrasonic or wet tumbling). The brass is pink because in that area of the surface, the zinc has been removed from the brass somehow, leaving mostly copper. This can happen with wet cleaning using acidic cleaning solution. Usually, however, the affected area is much larger. Since it's such a small area, it makes me wonder if you had some small amount solvent in your chamber, or it is getting on the brass from somewhere else.

Either way, if you can't feel it by running a fingernail over it, then it's just on the surface and shouldn't be an issue. I get it when I leave the brass in my ultrasonic too long - except it's over the entire neck of each case.
 
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The reason I asked was to see if you're wet cleaning (ultrasonic or wet tumbling). The brass is pink because in that area of the surface, the zinc has been removed from the brass somehow, leaving mostly copper. This can happen with wet cleaning using acidic cleaning solution. Usually, however, the affected area is much larger. Since it's such a small area, it makes me wonder if you had some small amount solvent in your chamber, or it is getting on the brass from somewhere else.

Either way, if you can't feel it by running a fingernail over it, then it's just on the surface and shouldn't be an issue. I get it when I leave the brass in my ultrasonic too long - except it's over the entire neck of each case.
Good to know. Thank you. There's a chance im not getting 100 percent of the solvent when cleaning my barrel/chamber. I'll have to make sure im getting it all and not missing any tiny areas