newRem 230g FMJ -larger-brass color?

My last order of 230g Rem FMJ bullets are brass colored instead of copper colored. - And they mic' about .001" larger diameter on my cheap calipers.  -- Has anyone used these brass colored bullets?
Before I order more - Comments? -- Barrel wear: brass vs copper?     -- - - Thanks in advance, Russ

Any updates from anyone?

From a Machinists viewpoint (not being an Engineer).
Brass is copper alloyed with zinc that gives it "free machining" properties making it cut very easily (or in other words good lubricity going down the bore).
Copper wants to gall while machining and tends to stick to the cutting tool (barrel).
I like using Montana Gold bullets, which contain more zinc, for this reason.

Wes, 

Have you found MT Golds to be accurate at 50?  I'm trying to figure out which bullets are working for people. 

With components so hard to find, flexibility seems a virtue. 

I just ordered Hornadys. I cannot find Magnus/ Zeros.

Hi Dewey,
I tested them in a RR and they shoot just as good as Remington and Sierra's (Kart barrel).
During this testing figured out that they don't group well if you shoot them through a copper fouled barrel (after the Rems and Sierra's). Had to JB the bore to remove the copper then they shot good again.
I like them because they are well made and easy to get in Washington State. MG 185gr JHP's are also as accurate as Nosler 185gr JHP's.

I would not be concerned at all about brass wearing a barrel any more than copper. There are a lot of people, myself included, shooting .224 diameter bullets formed from a fired .22 LR case and a lead core with no problems.