brass discoloration question

[Russ257]

So I took my fist step towards reloading today and I tumbled all of the once fired factory brass I had. My father and I have been saving brass for years so some of it may be older. I the majority of the federal rounds had some discoloration around the neck. Almost looks like rust. The Remington ones didn't have nearly this amount.

Here is a picture

The two rounds on the left have the discoloration I am speaking of and the two on the right don't

Here is a link to the full resolution Picture so you can see better
Brass Full Size Picture

Is this just a cosmetic blemish or is it a structural defect. I tumbled them for an hour in walnut media. Should I tumble them longer or should It discard them? Any help is much appreciated.

 

[former naval person]

Re: brass discoloration question

Rub them with some 0000 steel wool or Nevr-Dull. They'll clean up fine. JMHO

 

[5R Milspec]

Re: brass discoloration question

or you can use a scotch brite pad.I like the pad because it doesn't break up as much.but it will clean up the spots you are talking about.JMHO John

 

[Fuzzball]

Re: brass discoloration question

Or just forget about it and shoot 'em!

 

[Russ257]

Re: brass discoloration question

sweet I hit a few with a scotch brite and they cleaned up just fine. Thanks

 

[918v]

Re: brass discoloration question

It's brass corrosion. It'll clean up with steel wool.

 

[btm_54]

Re: brass discoloration question

Dillon Rapid Polish 290 in combination tumbling longer is what I've done

 

[MitchAlsup]

Re: brass discoloration question

A: The discoloration around the neck is nothing to get worried about, just tumble them for another couple of hours.

B: Notice the ones on the left have a lot bigger expansion in the web area than the ones on the right. Thus the ones on the left were at much higher pressures and may be a stronger brass (or both).

C: The sholder edge is also more pronounced on the left--another indication of higher pressure (not out of range pressure just relatively higher than the ones on the right).