No offense intended, but again I question your sources. Unless someone is willing to test-fire these things against human-analogue targets in the presence of myself or trusted individuals such as Turbo, Astronuc, or Ivan... I call ********. Nothing other than a micro-fused explosive round can penetrate body armour and then expand to devastating levels in the tissue behind it. While theoretically possible, it is not going to appear in small-arms ammunition. That is in anti-tank territory. Until proven wrong, I stand by my assertion that someone is snowing you.
edit: The ******* above was originally a synonym for "bovine excrement". That autocensor is irritating.