Quote Originally Posted by Gman
M855=5.56x45 Mil-Spec ammo with a steel penetrator.
A good source of info regarding ammo:
The AR15.com Ammo-Oracle
whoah... holy sh*t. are those legal? i gotta get me some of those. i am just using old surplus .223s. if my ammo did that to 1/2" steel i wonder what those would do. probably want to step up to 3/4" for those