Wet tumbling emrittles brass?

[fatelk]

I'm hesitant to post about this, because I know I'll catch heck for it, but here goes anyhow.

I started a thread a while back about a bunch of .223 ammo I loaded a year or so ago, that was all cracking in the neck area when fired. I was trying to figure out why. The only real difference in my loading recently was that I started wet tumbling a couple years ago, and some surplus powder in those particular loads. I looked at the dies, and a replaced expander, wondered if that could be a factor, I don't know. Now I have some .270 brass from a year or two ago, that about half of it cracked in the necks when fired. Different powder of course, but also wet tumbled.

I know a half dozen guys will now tell me that it's the brass, brass wears out, and I just need to anneal. That or there's some ammonia or something hiding around my loading area somewhere (not). That's fine, except for the fact that this is something new. I've had cracked necks before, typically in 20 year old reloads, not in recent reloads. In looking around online, I've seen at least a couple others complaining about increased brass cracks after wet tumbling.

I can't say for sure, and it seems like most everyone says it can't hurt the brass. That may be true, I don't know. All I know is that I have brass cracking like it never used to, over decades of loading. Maybe it's something else. All I know is that I'm going to go through any rifle brass that I've wet tumbled but not loaded, and anneal it all. I also used to tend to tumble longer than needed, and used more Lemishine than necessary. Any brass I tumble in the future will get a much shorter ride in the tumbler, maybe an hour instead of three or four.

I'm really not looking forward to finding more wrecked brass as I go through more ammo that I've loaded in the last couple years.

[StuBach]

I don’t reload much necked cases so I can’t speak much on the annealing issue or what not but I can say I only wet tumble my brass for 10-15 minutes and they come out nice and clean. Might the extended time have something to do with it?

Also, in my experience the brass I’m finding lately is much lower quality than the brass of yesteryear. I love finding old cases of WWII military surplus brass cause I know it will withstand tons of reloads but modern brass seems to fail much faster.

Just 2cents from someone far less experienced so feel free to trash or treasure.

[15meter]

Work hardening from impact of the stainless steel pins?

I know there is a mechanical plating process that uses impact to plate parts. Too long in the polisher with marginally hard brass to start?

Just kinda what iffing. I've never wet tumbled brass.

[JimB..]

I’ve got some 223 that’s a year or two old, brass was all wet tumbled. My situation isn’t comparable though because I anneal everything. I’ve got 45-70 that’s wet tumbled and older, never annealed, and it’s still fine.

Fatelk, you have something going on.

[fatelk]

Work hardening from impact of the stainless steel pins?

That's kind of what I was thinking, at this point. Sorry, I didn't mean to come off as quite so defensive. It's been a rough day, and I guess from past experience I expected a lot of people telling me how wrong I am.

[Elroy]

The zinc in brass can be bled out of it after some time in water, but what you want to avoid is salt LOL.I say that because I tried a YouTube recipe of water vinigar,and salt once ,and I ended up with greenish yellow water,and pink brass.LOL.

[edp2k]

Unless your brass is very pink, you didn't remove any zinc.

[Elroy]

Unless your brass is very pink, you didn't remove any zinc.

You Sir are a natural born poet. LoL

[fatelk]

I’ve got some 223 that’s a year or two old, brass was all wet tumbled. My situation isn’t comparable though because I anneal everything. I’ve got 45-70 that’s wet tumbled and older, never annealed, and it’s still fine.

Fatelk, you have something going on.

It's definitely something, but honestly I've been through absolutely everything I can think of and this is all I can come up with. Interestingly enough, I have some 45-70 that was also wet tumbled. We just shot 20 rounds a few weeks ago and no cracks. I have some 30-06 that I fired through the M1, and no cracks. I may have annealed that brass though; I don't remember.

I did an experiment with the .223 brass. I pulled down the ammo with the problem brass. Some was cracked before firing, and all cracked after firing. I picked out some unfired that wasn't cracked, and annealed them. They fired fine without cracking. It sure appears to be a work-hardening thing.

Either way, I'll be tumbling for a shorter amount of time, and annealing rifle brass.

[fatelk]

When I first got the tumbler, I kind of went nuts with it. I had this silly idea that the brass needed to be super shiny inside and out. It has a 3-hour timer on it so I ran it for 3 hours. The timer gets stuck sometimes, so I had some lots in the past that ran for 5 or 6 hours. I wonder if I'm finding those particular lots now.

[Dusty Bannister]

Which head stamps are splitting? Some just seem to be more likely to fail than others.

[JimB..]

Work hardening comes from stress, and the cases sliding over each other and some pins under water really doesn’t put much, if any, pressure on the brass.

Super shiny brass does like to grab on the expander, but I don’t see how that would create a problem.

I’ve tumbled for as long as 12 hours once when I got called away, that 223 brass has been fine. Hmm, I might have annealed it. Once I bought the Giraud annealer I’ve kinda gone nuts with it each winter when the shop can use the heat anyway.

You should take a few pieces of old brass and soak them in a heavy concentration of lemi shine so you can see what the color change looks like. I doubt that’s your issue, but good to have first hand experience. I find that the lemi shine concentration isn’t critical when wet tumbling, but is when ultrasonic cleaning.

You should take 200 pieces of brass, load them identically, fire them, then divide them in half, one half gets dry tumbled the other wet. Keeping each group together repeatedly load, fire and clean until you get 50% failure. That’ll tell you if wet tumbling is your issue.

[Leadmad]

faltelk, I've also thought the same with wet tumblers work hardening our brass and have on occasions had a friend anneal cases for me in his AMP annealer who provided the write up link I've attached, hope its going to put your mind at rest and cheers

https://www.ampannealing.com/articles/40/annealing-under-the-microscope/

[fatelk]

I don't think it's the Lemishine. I've seen and had pink brass before, and that's not the case here.

I've pulled nearly 1,500 rounds, and about 80% were cracked when I pulled them. The other 20% crack on firing, unless I pull and anneal then before firing; then they don't crack. The headstamps are a range mix. In my hand right now I see LC15, PMC, LC14, WCC04, AGUILA, FC12, LC12. The majority is recent manufacture LC. I've never had nor seen a 100% failure rate like this before, in ammo loaded for a year. Whatever it is, I've hashed it over too much already. I'm just going to anneal all rifle cases I load from now on, if there's any question about it.

By the way, as I mentioned in the other thread, it's not a chamber problem; they crack when fired in 4 different rifles.

[lightman]

You have a mystery going on, for sure! I would not think that a short tumble would work harden brass. Maybe when your timer sticks and they tumble longer, but I'm still doubtful. I tumble for 2 hours and have not had this trouble. I have heard that longer times in the tumbler can "peen" the case mouth.

I have had new Winchester brass get neck splits on the first firing and this caused me to buy an annealing machine.

Good Luck figuring this out.

[country gent]

Im wondering if the stress relieg process of heating and cooling the cases would help. At work some tooling Angle plates cee blocks and other things. we would give them a treatment over 1-2 weeks. When you went home you set the in the shop freezer ( -60*) and when we came in the next day would set it out for the shift to warm. this was done every day the last 3 to 4 days the part was taken to the heat treat and warmed to 200*. These were much more stable after this. when finish ground they didn't move or shift Like they did when grinding in after heat treat. Also they stayed on longer before needing touched up.

On the cartridge brass cases the annealing may be relieving these stresses along with softening the cases. Many things can cause stress and hardening of metal. bending or harmonics patterns, peening. I cant see wet pin tumbling causing a lot of stress but there is the chance that at the right rpm and load the vibration pattern may be right to set up some. I cant see the lemishine or dawn chemically causing tis but other soaps may contain small amounts of ammonias or salts that could.

I have always used corn cobs so the above is just my thoughts on it

[Drew P]

Work hardening comes from stress, and the cases sliding over each other and some pins under water really doesn’t put much, if any, pressure on the brass.

Super shiny brass does like to grab on the expander, but I don’t see how that would create a problem.

I’ve tumbled for as long as 12 hours once when I got called away, that 223 brass has been fine. Hmm, I might have annealed it. Once I bought the Giraud annealer I’ve kinda gone nuts with it each winter when the shop can use the heat anyway.

You should take a few pieces of old brass and soak them in a heavy concentration of lemi shine so you can see what the color change looks like. I doubt that’s your issue, but good to have first hand experience. I find that the lemi shine concentration isn’t critical when wet tumbling, but is when ultrasonic cleaning.

You should take 200 pieces of brass, load them identically, fire them, then divide them in half, one half gets dry tumbled the other wet. Keeping each group together repeatedly load, fire and clean until you get 50% failure. That’ll tell you if wet tumbling is your issue.
Super shiny brass that holds on to the expander,, because of galling on the ball, which could leave long vertical and pretty deep scratches in the brass, making weak points and leading to neck cracks.

Were the failures vertical?

[cupajoe]

Years ago I bought some once fired LC 308 brass from Dillon. I processed all the brass, loaded it all and put it up in an ammo can. A few years later I opened the ammo can and could smell the IMR 4895, probably 75% had split necks. I fired a couple with necks that had not cracked and they split at the neck upon firing. I only dry tumbled with corncob.

[starnbar]

I have had the brass issue too and it could be from tumbling or just brass that wasn't annealed long enough I use all most all gi brass and certain lots will split about half the necks tend to think its in the manufacturing end as it was only gonna get shot one time out of a military weapon. for what its worth maybe yes maybe no

[owejia]

Would think the gentle rolling of the ss pins and brass would also peen the brass, peening is used some times to relieve stress in steel after welding.

[blue32]

To offer a comparison, my FL sized 223 will generally achieve neck cracks at 20% of the lot on the 9th reload. I typically toss the lot at that point. I dry tumble and the rounds are fired in an AR. I've noticed LC, Federal, Aguila, Rem and PPU to have fairly consistent failure rates.

[onelight]

Many people wet tumble brass with pins with no excessive splitting after many cleanings some with huge timber's with many more pounds of brass and pins that would greatly accelerate any work hardening from peening.
To my uneducated brain it would not be the process of rolling a few pounds of bass and pins in a small container dampened with fluid , if so this would be a common problem to many of us.
It will be interesting to see if a solution is found. :popcorn::popcorn::popcorn:

[modified5]

Interesting thread. I only dry tumble with a small amount of Cabela's polishing compound in it. A whole bunch of years ago I bought 1000 once fired military brass to feed my ground squirrel addiction. We used to go out almost every weekend and shoot between 500-1000 rounds of various .22 rounds. I would spend the next week reloading and buying more 22lr for the next weekend. All the .223 got full length resized because it was used in multiple guns. I never annealed the brass. My failure rate was really low. I did have one piece of lc68 that finally had a complete head separation after who knows how many reloads. Took a cleaning rod to get the body out.
I can't imagine wet tumbling having that big an impact, but I have been wrong before. :coffee:

[fatelk]

I’m not entirely convinced that it’s the tumbling; I just don’t know what else it could be. In my mind, the nearly 100% failure rate in widely mixed brass rules out an inherent brass problem.

I had a batch of .222 ammo that all cracked the same way once, long before I ever wet tumbled. It had sat for about 20 years. I also had some 30-06 rounds where a lot of them cracked too. They had also sat for 20+ years. I never annealed back then either. I made the assumption that this happened due to used, unannealed brass sitting loaded for years and years. This .223 ammo sat for just a year.

[leadhead 500]

I can promise you that it’s not the wet tumbling causing the brass to split. I wet tumble everything I load for now days from 223 to 50 Bmg in a 15# rotary tumbler using stainless Steel pins, Lemi shine, a small squirt of dawn and hot water. I run them for around 30 minutes and take them out and dry them. Over the years of reloading thousand and thousands of shells and most of the case cleaning was done with a vibratory tumbler and media, I have no more neck splits using the rotary tumbler compared to the vibratory tumbler. I have run into seeing many thousands of Lake City brass being harder than a lot of commercial brass

[bigboredad]

I have a few friends that wet tumble and at first they used the lemishine steel pins and all the recommended recipe. After about a year doing it they quit using everything except dawn dish detergent.
They are all brass hounds and pick up everything they find and they tell me the dawn gets them looking brand new even primer pockets.
They also use a dehydrated to dry their brass

Sent from my SM-T377V using Tapatalk

[salpal48]

I have beens saying This for several Years now. Pin tumbling will ruin Brass. Like most Loaded I use the same batch of brass over and over again. After Firing i would tumble clean with Pins , water and citric acid. after a wile I noticed the brass would Have an Orange Peal Effect On them. Micro dent that You would Feel @ the touch. Upon firing the micro dents brass would Blow out and leave the Brass somewhat " Frosted".. then i would dump them.. ater that went back to media . Never happened again

[Seeker]

If you used too much lemshine your brass would be pink also.

[dbosman]

Having wet cleaned a ton of brass, literally a ton, I have opinions on wet tumbling. I stop at two hours. I advise the use of a timer.
If you look at the case mouths, after cleaning, you can see serrations from the case edges hitting case edges. If you look at your wash water in bright light, you'll see flecks of brass or light glinting off the flecks. Dirt is being removed, as is the patina, but also enough brass to see those flecks. I never thought of trying to mark and weigh cases, but some brass is coming off.

Could the pounding that is removing some brass be enough to harden the cases?

[Four-Sixty]

I wonder if tumbling in pins introduces galvanic corrosion. After all, we have dissimilar metals in an acidic solution.

We should track the results as JimB suggests.

[onelight]

I wonder if tumbling in pins introduces galvanic corrosion. After all, we have dissimilar metals in an acidic solution.

We should track the results as JimB suggests.
That is an interesting thought . Would the pins be brass plated if this was happening ?

[Fireball 57]

Merry Christmas, Everyone! My range pickups of brass gets a dry tumble of about three hours in cob media ie: not news media. This removes surface sand and some corrosion. Separating and sorting the cases, eliminates defects. Selected cases are deprimed,sized, deburred and chamfered,ready for a boiling bath on the kitchen stove,of four minutes, then a cool water rinse and in the oven to dry at 260 degrees for 15 minutes, air cool, ready to load. All without steel pins. With a couple tablespoons of Lemishine, a dash of Phosphate-free dish soap AND a splash of liquid cheap car wash, my Dillon purrs like a kitten. NO split cases. No harm or foul. Have a great day! Fireball 57

[10mmShooter]

Industrial shot peening is a process used to remove residual stresses in metals. Just isolating the tumbling of brass with the ss pins. This is a net removal of stress in the brass. If anything it would make the brass softer. But in general its assumed the impact and action of our wet tumblers is no where near the impact and energy involved in "real" industrial shot peening. Hence no effect on the brass structure. Easy to test this hypothesis take a few pieces of factory new brass cartridges, as the control, then take a like sample and wet ss tumble the crap out of them for some unrealistic number of hours in the tumbler. Then send the two samples off to a materials lab and have the brass tested for composition and tensile strength and hardness. Only way to know for sure. I assume RCBS, Lyman may have already had this done this ?? who knows call and find out.

[igolfat8]

I agree with 10mmShooter. It’s common to stress relieve weldments using a needle gun to impact the fresh weld with thousands of impacts. So there is a tiny correlation between the two processes but as mentioned the SS pins don’t make an impact that is nearly as forceful as a pneumatic powered needle gun but one could conclude that it would tend to soften as opposed to harden the brass.

I wet tumble and shoot mostly 9mm open brass, which is a high pressure round. I shoot at least 15K rounds per year so 8 process a lot of brass. Rarely do I find split brass cases. However, I do find that nickel cases split with predictable regularity. I only get one or two reloads on nickel cases before they split. I’ve read where the nickel plating makes these cases harder so maybe there is some correlation to hardness and cracking?

[fatelk]

Steel and brass are two very different metals, so I'm not sure what that tells us.

I will say that I've tumbled a lot of straight wall cases: .30 Carbine, .44 Magnum, 9mm, .40 S&W, .45 Colt, etc.. Some of them, especially .45 Colt and .30 Carbine, have been tumbled more than once. I haven't noticed any cracking in them. So far, the only unusual cracking has been in .223 and .270, but those were also the only ones that sat loaded for any length of time. The 100% failure rate of the .223 ammo is the mystery I can't figure out. It's clearly work and/or age hardening/embrittlement, since annealing helps. Why exactly? I don't know. I'm not completely convinced one way or another about wet tumbling.

I'll still use my tumbler. I just did an experiment. I tumbled some brass for 45 minutes, with just a light sprinkle of Lemishine and a squirt of Dawn. It came out fine. One piece of range brass that was pretty tarnished wasn't quite as shiny as I'd like, and the primer pockets weren't quite spotless, but in reality it's all fine. I'm convinced that I was tumbling far longer than necessary. Does it hurt? I don't know, but from now on I'll tumble less and anneal anything that's likely to sit around very long. That's my plan. :)

[Traffer]

The zinc in brass can be bled out of it after some time in water, but what you want to avoid is salt LOL.I say that because I tried a YouTube recipe of water vinigar,and salt once ,and I ended up with greenish yellow water,and pink brass.LOL.

Yup I did something similar but not with salt. I think I used some other kind of caustic stuff in the tumbler...Got pink brass...brittle as hell.