Just a wild guess, the steel allows for better barrier penetration and will separate from the alloy on a fleshy target so at minimal you will at least get 2 or 3 part fragmentation. Could be some level of BS on the media for a the man stopper part and just be a good penetrator and still zip right through a badguy leaving a .22 hole.
I don’t buy the U.S. military might....
An E.M.P. would reduce our technological advantages to scrap metal in a blink of an eye.
We are not prepared for the inevitable and the terrorists know it!