Ammo 'rainbow' discoloration

[Yama Arashi]

Pardon me if this isn't the right section, but I didn't see any other section specifically related to ammunition.

I purchased a small bulk quantity of some older 168gr Federal GMM, and the cartridges in one of the boxes have some fairly drastic discoloration. Basically a rainbow color all the way from one end to the other, bullet included.

I'm aware oxidation occurs and discolors the brass, but I've never seen it to this extent

Has it been exposed to high temperatures, or been handled and had a reaction to acidity, etc? Safe to shoot?

I don't feel like blowing anything up.

 

[TheLion]

Re: Ammo 'rainbow' discoloration

 

 

[Temp9]

Re: Ammo 'rainbow' discoloration

Doesn't look like annealing (proper annealing anyways). Looks like oxidation to me. Probably just age and humidity. I had some old 9mm that started to look like that.

 

[TheLion]

Re: Ammo 'rainbow' discoloration

I have federal xm855 rounds in a just opened tin that look very similar to that. Hence my post. I'd still check with a local gunsmith for a more professional opinion. Pictures can be tricky.

 

[NC Cruffler]

Re: Ammo 'rainbow' discoloration

chemicals in the cardboard box cause that

 

[Dracozny]

Re: Ammo 'rainbow' discoloration

oils in your skin will have similar effect over time.

 

[AR-180]

Re: Ammo 'rainbow' discoloration

That ammo is fine. I think most of us have shot lots of rounds that look worse.

 

[leadbullet]

Re: Ammo 'rainbow' discoloration

tumbled it for a few hours and they will look like new again and just fine to shoot,

 

[Beef82]

Re: Ammo 'rainbow' discoloration

I agree with the majority above, normal oxidation from exposure to whatever enviromentals. Seen it from handling happen rather quickly, other times no obvious effect for years, regardless, it hurts nothing, and a trip thru the tumbler would remove it.

 

[GlockandRoll]

Re: Ammo 'rainbow' discoloration

I store my ammo w/a silica gel pack to prevent this.

 

[ORD]

Re: Ammo 'rainbow' discoloration

You can tumble it if you so desire, but it isn't necessary. Even without handling, it has been my experience that Federal brass is so soft that it generally will get marks similar to that from just sitting around in the packaging for a while (which this apparently has been sitting a while bc that is the OLD packaging for FGMM...can't recall when the switch was made). No harm and it is perfectly safe to shoot "as is."

Good luck!

 

[Yama Arashi]

Re: Ammo 'rainbow' discoloration

Thank you for the replies.

I'm not concerned about the aesthetics whatsoever - just wanted to be sure it hasn't been compromised to the extent that I'm risking a rifle for a -$20 box of ammo.

That packaging is from sometime in the 90's, but I don't recall if it's early or late 90's. I also have some that's in the blue and gold packaging, as well as the latest box with the graphics and what not. This was the only box that had discolored cartridges.

 

[Ledzep]

Re: Ammo 'rainbow' discoloration

Oxidation. Even the color you see on annealed brass is from oxidation, with heat being a catalyst.