question about dark brass after polishing, also old .45 ACP headstamp

[1KPerDay]

I just cleaned a batch of old mixed brass I found in a box, lots of .38 special military stuff from the 50s and 60s, vietnam-era 5.56, 1952 .30-06, and some .270. 2 cases were almost black when I put them in, one .270 and one .30-06. I'm curious what causes this. They remained black after 8 hours in walnut media; they're shiny now but still dark unlike the rest.

Also anyone know what F A 28 headstamp is on the .45 ACP cartridge? And VPT 41 on .303 british?

thanks

 

[ReloaderFred]

The black is just regular old brass tarnish. You can clean it several ways, but I use citric acid.

The F A 28 headstamp means it was made by Frankford Arsonal in 1928.

Hope this helps.

Fred

 

[rondog]

The black stuff is oxidation, regular tumbling won't get it off, just makes it shiny. I've picked up a lot of it, and have to soak it in a solution to eat the crud off. This stuff works well but it's expensive, about $25/gallon plus shipping and maybe hazmat fee too. Maybe you can find it locally, and in a smaller size?



You can also make a solution, but I can't recall the recipe offhand. If you don't have a lot of it, you could try wiping them with lemon juice, citric acid eats that crud off. I've even soaked cases in unsweetened KoolAid, it works too.

I've gotten cases like these to look like new, but I'm just that anal. Most guys would toss 'em in the scrap bucket.



The FA28 .45acp is a Frankford Arsenal, I believe, made in 1928. I personally would keep that one for a souvenier. The .303 was made in 1941, don't know the maker.

 

[marukka]

You can make your own Iosso fluid for about $1 per gallon. 5% detergent (dish soap works well), 4% phosphoric acid, 91% water. Email them for the MSDS is you want to double check.

 

[rondog]

You can make your own Iosso fluid for about $1 per gallon. 5% detergent (dish soap works well), 4% phosphoric acid, 91% water. Email them for the MSDS is you want to double check.

Thank you! I've got that printed out now....

 

[evan price]

Cases with light brown tarnish can be saved with immersion for about 15 minutes in plain white vinegar. Then rinse in hot water to remove the vinegar.

Stuff like Rondog has in his picture I save by mixing a solution of vinegar, Dawn soap and water in a bucket, pour in the brass, and put it in the back of my truck while I drive to work and back. (Free agitation). Then dump, soak in white vinegar for 15 minutes, then rinse, dry in the sun, then tumble in walnut and NuFinish.

Although for common stuff like 9mm and 40 S&W I just often scrap it unless I really need it.

One thing to know-

A process called "Selective leaching" happens when alloys containing brass are in contact with water. The brass alloy looses zinc (Brass is Zinc and Copper alloyed). The resultant brass is spongy and brittle. An inidicator of this is a color change to pink or reddish tint. If it looks pinkish or the tarnish is a plum color it is not worth saving it no matter how nice it is otherwise. Simple brown tarnish, can be saved, but any pink staining or spots is zinc leaching and it is not safe to save ten cents on a case and have it fail. Rifle cases, especially, are under enough pressure that I won't try to save them. Handgun brass, sure, but I only do it with 38 Special or 45 acp.

 

[1KPerDay]

Thanks guys. Some of my '06 cases do have small pink spots. I'll toss those.

 

[longdayjake]

Don't toss them. Send them to me.

 

[1KPerDay]

You think they'll be fine?

 

[ColtPythonElite]

I've got a good percentage of dark brass mixed in my .45 supply. I don't worry about it. It all shoots the same.

 

[bdejong11129]

I dont tumble my brass. Instead I have a big bowl that I use a good squirt of dawn detergent and a large splash of white vinegar from walmart. I agitate them for a few minutes, let them soak for about 10 and then rinse them off and let them dry.

They come out better than they went in, the water is dirty and black and then function perfectly. I mean, they go in the press, into a plastic box and then into a magazine and then boom, they are dirty again..

 

[longdayjake]

I wouldn't be worried about shooting them at all.

 

[Sunray]

Brass needs to be clean, not shiney.
"VPT" is Valtion Patruunatehdas, Lapua, Finland. Doubt the '41' is the year. Finland was on the other side in 1941. Suppose it's possible though.

 

[Fishslayer]

The F A 28 headstamp means it was made by Frankford Arsonal in 1928.

Looks more like '82 to me, but my eyes are old...

Might want to run a magnet over that dark brass. Some might be steel.

 

[ReloaderFred]

Nope, it's F A 28. I've got a bunch of the old Frankford Arsonal .45 acp brass and ammunition and it's all marked that way. Besides, Frankford Arsonal wasn't making brass in 1982, since it closed in 1977.

Hope this helps.

Fred

 

[Watergoat]

That VPT probably was made in 41. I seem to recall reading that they had a bunch of Brens, and maybe some Maxims. May have even had some SMLEs. Along then, everybody was scrambling for small arms, anything that would go bang. I wonder if the Germans sent the Finns some of the arms they captured at Dunkirk?