once fired .223/5.56 brass

[rg52]

Are there any brands of previously fired brass that one should stay away from?

[bohoki]

just the obvious like the steel or plastic or berdan primed cases

[Linus]

All brass is good, although I've been tossing most Federal brass I find since I've noticed that the primer pockets get loose faster than other manufacturers.

[popeye4]

You probably should also be concerned about what it was fired in. Brass ejected from SAWs or other machine guns tends to be stretched more than you want.

[popeye4]

Also, check this out: http://www.zediker.com/downloads/oncefired.pdf

[Bill92869]

More advice: Be sure to check for crimped primers. You'll need to swage the primer pockets to open them if they are.