Ultrasonic case cleaning

[snuffy]

I'm going to do a little test this afternoon, in some ways just to satisfy my own curiosity, but also to help answer this question; can an ultrasonic cleaner get both carbon AND lube off a bass case?

Back when I got the cleaner, I tried some brass in it with various cleaners. The Birchwood Casey cleaner worked best, but they were dry, no lube on them. It got the carbon out of the primer pockets AND the inside of the cases.

http://www.midwayusa.com/viewProduct...tNumber=311703

Anyway, I'm working on a long range load for a buddies target AR-15. I'm using Lapua brass, I have some that's once fired that I will size using the FA spray case lube. Then give it a couple of 8 minute cycles in the Harbor freight ultrasonic cleaner. BRB with the results.

I sized them using the frankfort arsenal spray case lube, sized in a Hornady FL sizer, then they went for 2-8 minute runs, with heat, then a rinse in hot water.

Every bit of lube AND carbon inside the case was gone. The primer residues is all but gone, a few specks here and there. I think another 8 minutes would have gotten all of it. Also, the cases are nice and shiny, but not as shiny as they would be with corn cob & polish. Here's a few pics;






Difficult to see, but there's literally no carbon inside the cases. You can see the flash reflecting back a shine from the bottom of the primer pockets.

If you really HAVE to have the carbon out and the lube off WITHOUT a tumbler, this is the way to go.

http://www.ask.com/bar?q=harbor+frei...freight.com/

Also, this is THE best way to get a trigger group, whole bottom of a semi auto handgun or slide clean WITHOUT needing to disassemble it.

 

[ants]

Excellent work, Snuffy!

I put the brass in a glass jar with the cleaning solution, then set the jar in the ultrasonic with plain water. That works good too.

I do it that way because the ultrasonic doesn't belong to me (made for jewelry) and the owner doesn't know I use it for brass (she isn't a Forum member, so I think I'm safe).

 

[45ACPUSER]

http://www.6mmbr.com/ultrasonic.html is a great article. It is talked that a person should not put the glass containers directly on the bottom of the US cleaner?

 

[ants]

should not put the glass containers directly on the bottom of the US cleaner

That's the way we cleaned our technical pens for 30 years before we went to CAD drafting, as long as the glass container sits in water (not on the bottom of a dry basin).

 

[kelbro]

Nothing should touch the bottom of the US cleaner. It will destroy the 'vibrators'. It's not the vibration that cleans, it's the sound waves created in the water of the tank creating waves inside the container that your parts are in.

 

[essayons21]

I put pyrex containers on top of the plastic mesh screen that came with the harbor freight cleaner. I have heard that if you suspend the container in the water you get better cleaning.

 

[ants]

Nothing should touch the bottom of the US cleaner. It will destroy the 'vibrators'.

Ah, I understand. Yes, our ultrasonic unit has a mat on the bottom. The glass jar sits on top of that. My earlier reply didn't make that clear. Thanks, guys.

 

[snuffy]

In my US cleaner, there's a plastic basket that the brass was in. It's good to know that you have to be sure the object being cleaned is NOT in contact with the bottom or sides of the liner.

I'm not going to use it for brass that often, I run cases in my midway tumbler for most jobs. That stuff I did was for a match .223 AR-15 that I'm working up a load for 600 yd. matches. I'll continue to use it, because now I've introduced a new variable into the brass prep. My main concern is getting the brass dry after it's bath!

 

[otblue]

You don't say (or I missed it) what you are using as your cleaning solution but the photo suggests you are using AquaClean. I am using the AquaClean bore solvent to remove copper and it works very well. It contains the same ingredients as the foaming bore cleaners so it should.
I know Shooters Choice promotes the large container of AquaClean as a US cleaning solution but I'm not sure that includes brass. Cleaning gun parts is another ball game altogether.
I would be wary of using this for cleaning brass but you are using it only for short bursts ( 8 min)so maybe you can get away with it.
I use a 5% citric acid solution with a dash of any concentrated non alkaline detergent and this cleans lubed cases extremely well inside and out. Doesn't polish them just cleans them. Citric acid is safe for brass, even passivates it and helps prevents future corrosion.
I do clean for about 30 minutes though, in line with the recommendations in the article on 6mmBR.

 

[The Bushmaster]

My question for Snuffy is: Does removing the carbon from inside the case really improve accuracy? I've noticed that it only seems to coat it once and does not seem to build up any after the first firing...

 

[Walkalong]

I do it that way because the ultrasonic doesn't belong to me (made for jewelry) and the owner doesn't know I use it for brass (she isn't a Forum member, so I think I'm safe).

Adapt, improvise, overcome....I like it...

 

[otblue]

"Does removing carbon from inside the case improve accuracy".
I recall reading an anecdote from a 1000 yard rifleman who measured case capacity before and after ultrasonic cleaning. He claimed there was enough carbon to make a slight difference in capacity and hence accuracy. For the rest of us mere mortals I really doubt it matters.
I clean cases ultrasonically for 2 main reasons.
Firstly my "precious" cases, ones that I have prepared carefully with ONT, primer pocket uniforming etc and that I use bump and bushing dies with, are never tumbled, always US cleaned. After all that work I don't want to go and mess up my necks by bashing them together for hours. If you check out 6mmBR forum I think you will find that is the usual reason for using an US cleaner.
The second type of case I US clean are those I intend to store or may not use for a long time. I have found that reloads I made decades ago and have started to use often split their necks on firing even though they may have only been once fired previously. On the other hand new cases, even old military stuff pre WW2 is fine.
My speculation is that firing residue affects the case adversely similar to work hardening and the necks split. My concern is also what the rest of the case is like.
I am hoping that US cleaning of all firing residue will prevent this and I hope to live long enough to confirm.
That is also my reason to be concerned about the ethanolamines in AquaClean. These chemicals can cause corrosion in brass similiar to ammonia. Might be OK in the short term but who knows long term.

 

[snuffy]

To me, the aqua clean seems like a very slippery soap. Ummmm I looked up the MSDS for aqua clean, triethanolamines make up 11% of the mixture. I'm sure as h*** not a chemist, I have no idea whether AC is corrosive. If it is, why say it's okay for firearm actions, trigger groups.

I'd guess that the brass would show some outward appearance if it was being corroded. It came out shinier than when it went in.

As for whether getting the carbon out is necessary, I don't know. I just was reporting on what I found. I, myself, don't think it's a problem. I believe there's quite a bit deposited the first firing, but no build up occurs. Some are very worried about the primer residue, that was gone WITHOUT scrapping or other mechanical means of removal.

Otblue, what mixture do you use in your US cleaner?

 

[otblue]

google triethanolamine reaction with brass/copper. You will come up with warnings of potential corrosion. This does not happen with most other metals so it is good for trigger groups and other gun parts. I'm not a chemist either but the ethanolamines are manufactured by reactions which include ammonia and it may be breakdown products that are the problem. As it happens when I first started using AquaClean Bore Cleaner (which is not exactly the same ethanolamine) I contacted the company to see if it was safe to leave in the barrel overnight. The company advised against that practice recommending only 60 minutes at a time. That suggests that there may be some concern of reactivity over a longer period.
Don't get me wrong, AquaClean is all I use to clean copper out of a barrel now, no smell, no mess and relatively gentle.
Would you clean your cases with Sweets or other copper removing bore cleaner. Sure they'll be clean but what's happening to the brass.

I've settled on a 5% citric acid solution with a few drops of windscreen wiper detergent. Citric acid is cheap and reusable and passivates the brass preventing corrosion. I have the brass in the machine for 30 - 40 minutes depending on the load. The time is machine and load dependent, you need to experiment.
The brass just needs a rinse then allowed to dry.
I've tried a whole range of different solutions, vinegar, phosphoric acid, various other detergents and special ultrasonic cleaner solutions and keep coming back to citric acid. It's safe and doesn't need neutralising like vinegar.

 

[otblue]

Think of Brasso, cleans brass extremely well and for items like buckles and door handles it's first class. Just can't use it for cartridge brass which has to contain pressures in the 60000psi range because the ammonia content causes irreversible damage to the brass structure.
Despite that people have used and will continue to use Brasso on cartidge brass and most get away with it at least for awhile. It might simply show up as early neck splits.

 

[snuffy]

otblue, I did a little experiment to ease my mind about your concerns with the aqua clean. I took an old coffee cup, and some scrap 30-06 brass, filled it and put the brass in it. It's been a couple of weeks, the solution is turning blue, the brass looks like it is bleached. Definitely a chemical reaction taking place, I would surmise the copper is being leached out of the brass!

That's enough to make me NOT use aqua clean in my US cleaner when cleaning brass. I doubt it would affect the brass in the 16 minutes it is in the solution, then rinsed off and quickly dried, but why take the chance?

Thanks so much for the heads up on this. I will never stop learning about this hobby, especially when trying out new tech.

 

[ar10]

I had an ultra sonic cleaner from HF last year and didn't like it. It took way too long to clean the brass and was sort of a "pita" waiting for the brass to dry. I did the job though, the brass was clean inside and out.
My first batch of .308's, (1000), fired fine, but being a mere mortal, and having over 4000 more to clean I decided that I didn't really care that much how the bullets looked on the inside. So I just ran them through the tumbler like I always did and and then loaded them. When I shot them this summer they shot the same way.

 

[otblue]

Snuffy, I ran a similar test using the AquaClean bore cleaner and left a few drops on an old 303 case overnight.
It was not pretty in the morning, enough to convince me that AquaClean is an excellent bore cleaner but not really appropriate as a case cleaner. I think you are wise in taking the cautious approach to this.
AR10, I have several US cleaning units including a large commercial unit which would easily fit over 1000 large rifle cases. However I still tumble nearly all my pistol and most of my rifle brass. My reasons and specific preferences for US cleaning are mentioned in an earlier post. Drying cases is easy, in summer just place them in a pillow on the dash of your car and they will be dry by the end of the day. In winter just place the pillow case full of cases over your heating duct, again they will be dry overnight or at most a couple of nights. Unless you are urgently in need of reloads in a hurry then this is no chore at all.

 

[243winxb]

keep coming back to citric acid. It's safe and doesn't need neutralising like vinegar.

Citric acid, good choice IMO. Cleaning the inside neck area of the brass is a good idea for match grade ammo. The nylon brush seems not to get all the dirt out. When i lubed case mouths with a Qtip and Lee lube i noticed an expander or boatail bullet can trap the lube between the bullet and case wall, not good for accuracy.