The guy's name was Forrest Guth (not sure what rank he was by the end of the war), Easy Company, 506th P.I.R, 101st Airborne Division. The way he modified the Garand was filing away at a certain part of the action. It somehow allowed the gun to fire at full auto. And considering how hard it is to conrtol the gun at semi-auto, i think full auto would have given your armpit quite a bruise. He gave it to Cpt. Ronald Speirs, also in E. Company, who used it throughout the Korean War. Although extremely hard, this proves that it was possible.