As the co-owner of the gun center, Miller decided to try out target shooting with shotguns. She began with
skeet shooting in 1961, and entered the state championship in 1962, which she won. She repeated in 1963 and 1964 before deciding to skip the 1965 tournament. Miller began
trap shooting in 1965 and won the state championship in 1966, winning every state trap shooting championship except one (1973) through 1974. In
The Great Delaware Sports Book, Doug Gelbert wrote of Miller and shotguns: "There hadn't been a more natural pairing in Delaware since
Caesar Rodney climbed on top of a horse." She competed at the
Grand American Trapshoot, described as the "
Super Bowl of trapshooting," and won several world championships, being called a "fixture" of the event. Later in the year she participated at the Grand American Trapshoot again and won third in the Class tournament, recording a score of 195 × 200. In May 1970, Miller was named to the women's trap shooting
All-America first-team by
Sports Afield magazine, an honor she would later receive again in 1972 and 1973, as well as selection to the second-team three other times; she also earned selection one year to the All-American skeet shooting team, being the only amateur to receive selection to the All-America team in both events in the same year. In August 1970, she competed at the 250 Target World All-Gauge Skeet Championships with her husband and both her sons, having the top performance with a score of 99 × 100. Later that month, she tied for the women's championship in the Grand American tournament with two others, scoring 95 × 100. In 1972, Miller overall had the second-best score in the Grand American tournament, although she did not place top-three in any individual competition. The following year, she won the national All-Around Average Award and was selected by
Trap & Field, the publication of the
Amateur Trapshooting Association (ATA), as the second-best woman trap shooter in the U.S., behind
Punkin Flock. In her career, she averaged a target hit rate of .934. ==Death and legacy==