Brass corrosion after wet tumbling

[Hoons]

I tumbled for two hrs with dawn, then rinse and add 9mm cap full of lemi shine and tumble for 2 hrs. I rinsed and let it dry in the sun. Is the corrosion from not rinsing off the lemishine entirely?

 

[linkstate]

I can’t say what is causing that corrosion but holy cow that’s a long time. 4 hours with a rinse in between?

Are you using steel pins?

Was this once fired brass or brass you collected that had been outside for weeks or months?

I do at most one cycle at 30 minutes to an hour. Rinse thoroughly, separate pins and towel dry and let sit for a few days for the insides to dry. Then pack in those cheap Tupperware containers. Never had corrosion issues like that. I use dawn and a little lemi shine at the same time.

 

[4g64loser]

Insufficient rinse. And failure to dry the cases.

Roll the cases in a towel after you rinse. Lay em on a tray or other smooth surface in front of a fan or in the breeze outdoors.

 

[Hoons]

I can’t say what is causing that corrosion but holy cow that’s a long time. 4 hours with a rinse in between?

Are you using steel pins?

Was this once fired brass or brass you collected that had been outside for weeks or months?

I do at most one cycle at 30 minutes to an hour. Rinse thoroughly, separate pins and towel dry and let sit for a few days for the insides to dry. Then pack in those cheap Tupperware containers. Never had corrosion issues like that. I use dawn and a little lemi shine at the same time.

Yes I'm using steel pins and they were range pick up.

 

[Hoons]

Insufficient rinse. And failure to dry the cases.

Roll the cases in a towel after you rinse. Lay em on a tray or other smooth surface in front of a fan or in the breeze

That's what I was thinking. Are these brass safe to fire or should I throw them away? I'm thinking the corrosion possibly weakened the brass

 

[4g64loser]

That's what I was thinking. Are these brass safe to fire or should I throw them away? I'm thinking the corrosion possibly weakened the brass

Surface ugliness.

Tumble them for another half hour or so, then separate from media, shake off water, roll on towel, and place on tray in front of fan or in breeze outside. If there are still marks on the cases, toss em. If the marks are gone, you are fine and they were just nasty water spots.

My buddy thought he was helping me by pre rinsing some brass for me to tumble and he freaked out because it looked like yours. I tumbled it and it was fine, no marks when done and no signs of damage to the metal.

 

[guzma393]

Those look like deep water marks from not drying off excess water.

Why are you tumbling soap and lemishine at separate intervals? You're supposed to tumble with soap and lemishine at the same time, at 1 hour at most to get really shiny brass. Follow this process:

*For removing lube off cases or degreasing/degunking SS pins, do a pre wash by tumbling the cases in zep industrial degreaserand water for 15 minutes. Drain degreased solution and replace back SS pins and brass in tumbler. If cases or pins are not too greasy or gunky, then skip this step*

- Add 1/2 to 2/3s capacity of brass with SS pins in the tumbler drum. There needs to be ample tumble spacing for an effective tumble clean/SS polish. Fill the rest with water.

- Add 2 tbsp of dawn or carwash soap (I used armorall wax n shine, the wax further protects the cases from water spots and tarnishing over time) and add a 45 ACP case of lemishine/citric acid.

- seal it off and tumble for 30-45 minutes.

- drain off ALL dirty solution and check brass if it's clean. If it came out smokey, then SS pins and brass are gunked up, follow the degreasing treatment step and repeat the process until cases come out shiny.

- rinse the SS pin and brass with clean water and separate pins. Put the brass on a towel, and tumble dry off the excess moisture out of the brass by grabbing the towel ends, forming a "boat/hammock" and lifting one end, causing the brass to tumble to one side. Lift the other end and repeat x20 times.

- deposit the brass on a second towel and perform the "boat" dry tumble method again, only x10 times. Brass is now virtually dry, externally. Fan dry, air dry, or heat dry if desired.

Pics below for outcome:

 

[Harrys]

Not rinsed and dried properly I use Lemishine and dawn all the time and have not had that issue. Also, you only need a teaspoon of lemishine any more it is too much.

 

[erwos]

Yeah. Possibly too much lemishine period, incidentally. I only sprinkle a bit in. Dish soap should be your main cleaning agent.

Side note: I've stopped using steel pins entirely. Too much of a pain to get them all out, and I don't really care how my brass looks so long as it's (mostly) clean.

 

[Squaregrouper]

I once added too much Lemishine and ended up with a bunch of rose gold Grendel cases. There was an obvious pink hue to the brass.

 

[trickg]

I once added too much Lemishine and ended up with a bunch of rose gold Grendel cases. There was an obvious pink hue to the brass.

That's dezincification - commonly referred to as red rot. You see it a lot in brass musical instruments. Basically what's happening is that the zinc is getting dissolved out of the brass alloy leaving only the copper, and depending on how bad it is, it can really weaken the brass in those places.

It looks to me like there might be a bit of red rot going on in the pic Hoons posted.

One more reason for me to stick to dry tumbling.

 

[4g64loser]

But the wet tumbled ones is more shinier.

 

[trickg]

View attachment 423865
But the wet tumbled ones is more shinier.

True, and wet tumbled brass gets primer pockets and interiors all shiny too, but I'm not sure that any of that is actually necessary to create good functional reloads.

 

[4g64loser]

True, and wet tumbled brass gets primer pockets and interiors all shiny too, but I'm not sure that any of that is actually necessary to create good functional reloads.

Not necessary but I no longer have to mess with my primer pockets on my precision rifle reloads. I've noticed definite improvement in my consistency as the amount of crud in my dry tumbler is no longer a variable in my process. I only dry tumble to remove lube if I body size. If I am using my Forster BNBDs I just wipe the die wax off the necks and proceed with no second tumbling.

 

[John from MD]

Cleaning primer pockets was found to have minuscule effect on accuracy some years ago. If you want better consistency, uniform your primer holes.

 

[4g64loser]

Cleaning primer pockets was found to have minuscule effect on accuracy some years ago. If you want better consistency, uniform your primer holes.

I do. And my primer pockets. And debur the flash holes. And turn my case necks.

The issues I had were with lousy primer seating in grody pockets. Seating force has become more consistent.

Similar benefits in the way of removing "amount of crud" from the variable list in bullet seating. For ammo that matters, I want the necks clean. Some use neolube or similar (I have experimented with graphite lubes and with moly coated bullets) with good success but I get my best results with both surfaces naked.

 

[holesonpaper]

Just sharing my experience in case it helps someone.

I wet tumble my precision brass and was encountering a higher SD than I prefer - which my mark is 10fps SD or less. After going through my processes, I found that wet tumbling too long would peen or create a bur on the case mouth that my resizing die and even sizing mandrel wouldn't totally eliminate. For the effected cases, the fix was to use pin gauge and pay close attention to the inside chamfer of the case mouth. There's a ton of others who have encountered this problem on the net - so I'll spare all the details however I've changed my wet tumbling such that I don't tumble precision brass for anything longer than 30 minutes and I use much more stainless diagonal tumbling media (as in 5-7lbs). Some guys are tweaking the water that they add to the wet tumbler but I've not done that yet.

Again, this only applies to precision reloading. Not your average range load.

Just sharing the lessons I learned. You don't have this issue with dry tumbling in a vibrator.

 

[4g64loser]

Just sharing my experience in case it helps someone.

I wet tumble my precision brass and was encountering a higher SD than I prefer - which my mark is 10fps SD or less. After going through my processes, I found that wet tumbling too long would peen or create a bur on the case mouth that my resizing die and even sizing mandrel wouldn't totally eliminate. For the effected cases, the fix was to use pin gauge and pay close attention to the inside chamfer of the case mouth. There's a ton of others who have encountered this problem on the net - so I'll spare all the details however I've changed my wet tumbling such that I don't tumble precision brass for anything longer than 30 minutes and I use much more stainless diagonal tumbling media (as in 5-7lbs). Some guys are tweaking the water that they add to the wet tumbler but I've not done that yet.

Again, this only applies to precision reloading. Not your average range load.

Just sharing the lessons I learned. You don't have this issue with dry tumbling in a vibrator.

I've heard of this but I'm actually experiencing the opposite. It is easier for me to hold batch to batch consistency since wet tumbling.

I could hold ES under 20 all day long but my batch to batch average would shift (same temp/baro) slightly sometimes. Now, I am seeing less shift. With all same component lots, I am holding ES under 10 most of the time and under 15 all the time with averages moving less than the SD.