I noticed the story page info on flechettes... I could swear it's backwards.
Aren't flechettes supposed to be designed for emaciating flesh and not armor? A long, slender projectile tends to rotate and break up upon entering the body, often resulting in destruction of much larger areas than the calibur of the weapon. Shot at supersonic speeds, a (sewing) needle would have an entry wound only as large as the needle itself, while the exit wound could be many times greater as the projectile breaks up in the body. Hence, massive internal bleeding.
I think this because, correct me if I'm wrong, I though flechettes were banned by the Geneva Convention for just this reason.