The University Greys were in fact Company A of the 11th Mississippi Infantry Regiment. They did suffer 100% casualties in Pickett's Charge there at Gettysberg, 10 killed or died of wounds, and 21 wounded.

That you are descended from George Bird of Company K, I congratulate you. I assume you have, or at least have seen, Steve Stubbs book on the 11th, Duty, Honor , Valor.