brown spots in unfired brass

mrappe · October 26, 2014, 10:29 AM

About 8 years ago I bought a bag of Winchester 30 06 brass and did not use it. It was never taken out of the bag. I wanted to load my 7.65 Argentine so I bought a case forming die from RCBS that takes 30 06 brass. I was using this brass and noticed that in about half of the brass there were brown spots that look are rust colored. Now I don't know if i should use them. They have never been fired or in water so i am not sure why they have corrosion in them.

Thanks

mehavey · October 26, 2014, 10:55 AM

Brown spots like that are just surface oxidation/normal aging
-- no effect on strength or any problem.

.

**Unclenick** · October 26, 2014, 11:07 AM

Discoloration is extremely thin. If you had black spots with verdigris and white crumbly centers, then a I would suggest using a dental probe to check how deep it went. But in the before and after photos below, the deepest oxidation point I found was about two thousandths (dial indicator riding a dental probe) and not enough to render the brass unusable. All the reddish blotches you see are where zinc near the surface oxidized more than the copper, so the citric acid in the cleaning solution left copper visible at the surface there. This, too, is extremely thin, as vibratory tumbling in standard Lyman media returned it all to a polished brass color afterward. In other words, the pink color is no deeper than the amount of brass smeared or removed by polishing is anyway.

mrappe · October 26, 2014, 02:00 PM

Thanks for the info ! Now i just need to determine the right recipe for this gun.

cw308 · October 28, 2014, 09:24 AM

I give all my brass a good cleaning before sizing. Keeps the dies clean & sizing accurate. Try 0000 steel wool I use it every time to clean the whole case, works great

October 26, 2014, 10:29 AM	#1
mrappe Senior Member Join Date: January 29, 2009 Location: Texas Posts: 256	brown spots in unfired brass About 8 years ago I bought a bag of Winchester 30 06 brass and did not use it. It was never taken out of the bag. I wanted to load my 7.65 Argentine so I bought a case forming die from RCBS that takes 30 06 brass. I was using this brass and noticed that in about half of the brass there were brown spots that look are rust colored. Now I don't know if i should use them. They have never been fired or in water so i am not sure why they have corrosion in them. Thanks __________________ God is fluxing me which is good but it is not fun.

October 26, 2014, 10:55 AM	#2
mehavey Senior Member Join Date: June 17, 2010 Location: Virginia Posts: 7,210	Brown spots like that are just surface oxidation/normal aging -- no effect on strength or any problem. . Last edited by mehavey; October 26, 2014 at 11:09 AM.

October 26, 2014, 11:07 AM	#3
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,743	Discoloration is extremely thin. If you had black spots with verdigris and white crumbly centers, then a I would suggest using a dental probe to check how deep it went. But in the before and after photos below, the deepest oxidation point I found was about two thousandths (dial indicator riding a dental probe) and not enough to render the brass unusable. All the reddish blotches you see are where zinc near the surface oxidized more than the copper, so the citric acid in the cleaning solution left copper visible at the surface there. This, too, is extremely thin, as vibratory tumbling in standard Lyman media returned it all to a polished brass color afterward. In other words, the pink color is no deeper than the amount of brass smeared or removed by polishing is anyway. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

October 26, 2014, 02:00 PM	#4
mrappe Senior Member Join Date: January 29, 2009 Location: Texas Posts: 256	Thanks for the info ! Now i just need to determine the right recipe for this gun. __________________ God is fluxing me which is good but it is not fun.

October 28, 2014, 09:24 AM	#5
cw308 Senior Member Join Date: September 2, 2010 Location: Plainview , Long Island NY Posts: 3,863	I give all my brass a good cleaning before sizing. Keeps the dies clean & sizing accurate. Try 0000 steel wool I use it every time to clean the whole case, works great