Rookie reloading question

[Youngfreshtoodeath]

What's the deal with these casings. I got them at the range after the park rangers did there yearly shoot. The top of the casing dosent seem to want to come clean and almost feels thinner then the bottom. I don't want to reload these not knowing what's going on.

http://m1301.photobucket.com/albumview/albums/youngfreshtoodeath/null_zps1787d512.jpg.html?o=0&newest=1

I feel like a dummie asking but, yeah... What's up with these.

 

[Nipigon Jack]

My guess is that they have been annealed and that your are looking at the heat mark.
What caliber?
Dont' take my work for it. Let's see if others agree.

 

[Cleftwynd]

Might be just me, but the pic is rather small and poor, can you post a closeup?

 

[yomomma]

My guess, and it is a guess

Brass did not expand all the way to properly seal. I get a little bit of that on my 30-06 rounds

 

[Wired leader]

I don't know why, but every link I follow to photobucket brings me to that size of pic....and I can never get them bigger.
In regards to the OP...looks like they may of been annealed. Some cases are annealed at factory. I've bought new old stock cases that showed this..actually worse.
I use a SS tumbler and they clean up nice...not sure if a vibratory would do the same, but I suspect if left in long enough they would look almost as good.

I wasn't aware that they annealed straightwalled cases though.