I called the collector who gave me the two bullets and he said they were U.S. Springfield .58 cal., .562" dia. minie balls, with three grease grooves, cone shaped cavities and are different lengths. They are dropped bullets with no nicks or dig marks and are in excellent condition. He said confirmed the fact that they were found at the Palmetto Ranch Texas battlefield and are quite common.
Thanks again for bringing this to my attention because I would have surely labeled them incorrectly.