Had a wild hair today. Have been cleaning lots of 308 brass in tumbler. Some of this stuff is old and has that oily dirty feel.
I threw a cartridge in some Muratic Acid. We clean Hastolloy and Siliconized brass with the acid. It cleaned it quick inside and out.
For you chemistry majors, could this be an acceptable method to clean dirty brass? Any Chem problems with acid and brass?
I'm no chemistry expert but I have worked with Muratic for a lot of years.
First, any acid will clean and remove surface oxides (tarnish) from brass. A brief exposure is unlikely to do any harm to the alloy.
Second, Muratic is quite strong and difficult to completely remove even with vigerous flushing. I would suggest you flush and then soak in a baking soda neutralizing solution before drying and tumbling. And any splashes on skin or, especially, eyes can be devastating if not rapidly neutralized.
Third, the traditional acid soak for cleaning cartridge brass is simple vinegar. A couple hours or less soaking will do the job and be as easy to flush as it need be. And vinegar fumes are harmless and non-corrosive, unlike Muratic. Not only are those stronger fumes very harmful to mucus membranes, eyes and even skin, the fumes will also condense on any metal in the area and cause significant corrosion or rust. No matter its effects on the brass, Muratic has some bad downsides, really isn't worth the problems in my opinon. Use vinegar instead.
well, brass is an alloy of zinc and copper, zinc is reactive with HCl (muriatic acid), copper not so much. however, they're alloyed not separate and i'm sorry to say that one of the processes used to convert scrap brass to copper involves immersion in HCl and heating to a certain temperature until the zinc and other impurities are dissolved. at room temperature, there will be weakening of the alloy if not a change of surface material composition. or so one can derive from: Process for converting brass scrap to copper powder - Patent 4323390.
I, too, put some deprimed fired cases in muratic acid. Didn't like the smell, hazards, clean up; all in that order. A gallon of vinegar is cheaper less hazardous and cleans up great with soap and water.
Appreciate the kind words.
"DONT DO IT"
Was talking with Certified Welder friend and he uses Muratic Acid to clean metal. Said, as far as steel, it removes the oxidation.
Vinegar sounds safe. Just got a 1000 pc lot of LC 308 mil brass and it needs a good cleaning then tumbling. Didn't want to ruin new walnut media on this crappy (condition) brass.
thanks to the vast unpaid resources on GnG.
Why even try screw with messy chemicals that leave you with a sludgey waste to dispose of and might harm the brass or leave a residue in the cases you don't want?The problem of how to clean and polish brass easily and efficiently has been solved for a long time.
Vinegar is Acetic acid....Coca Cola has Phosphoric acid in it...
You are Not talking a Ferrous Metal here (Steel), Brass is a Non-ferrous amalgam and as such it is susceptible to weakening by Chemicals...most acids and Alkalis react Negatively with Brass / Copper/Bronze...etc.
I was hoping I got your attention the first time...But i'm not sure , so
PLEASE...Dont DO IT With Chemicals !!! Buy Cheap Corn cob Hamster bedding from Walmart and tumble away....Less than 5 bucks worth will last years...
I have had some experience with Muriatic acid some years ago...Unless you are very very careful with it (not sure about what it can do to brass) you can really get into a mess. It is nasty stuff and the fumes are really damaging to lung tissue as with most acids. I restore antique hit and miss engines and lots of folks use Muriatic to clean out rusted up water hoppers...works great but also poses a large health risk...I just quit messing with it all together.
Muriatic Acid is hydrochloric acid in a less than lab grade state of purity. You can get it cheap enough, but it will produce chlorine gas fumes. My ex-wife would get a nosebleed whenever they used the stuff in a lab. We use it in dilute form in chemstry class.
I used it to pressure clean a water well in Michigan by opening the well and pouring the stuff down. Then I stood on the top of the pipe while the acid worked on the rust in the well point. The pressure was enough that the chlorine was leaking around my rubber soles, but it cleaned the point and chlorinated the well at the same time. The alternative was to shoot a .22 down the well and blow the crud off the point or call the well guy to come and pull it. The acid seemed like the most reasonable choice.
As has been said, all chemical cleaners will deteriorate your brass to some extent. I'd say you are making the right decision in not using it.
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