He was chosen by the Bengals in the 1968 AFL allocation draft for the expansion Bengals. He was a starting outside linebacker for the Bengals during their first-ever season.[2]
Buncom was slated to be a starter for the 1969 Bengals. On the morning of the Bengals' opening game of the 1969 regular season, on September 14, his roommate, Ernie Wright, was awakened to the sound of Buncom calling for him and gasping for breath. Neither Wright nor paramedics could save him. He was 29. The cause of death was determined to be a pulmonary embolism.[3][4]
He was survived by his wife Sarah, later a principal in the San Diego Unified School District, and seven-week-old son, Frank James Buncom III. His former team, the Chargers, as well as the Bengals, established trust funds for Buncom's son.[5]
When the San Diego Chargers announced their inaugural hall of fame class in 1976, Buncom was one of the four inductees.[6]
Ron Mix, a San Diego attorney and former teammate of Buncom's, said, "I remember Frank as being the best of us, and I'm talking about as a person with high character."[7]
His grandson, Frank Buncom IV, attended St. Augustine High School, where he was an outstanding defensive back as of 2014 being recruited by many Division I programs.[8][9][10] On January 28, 2015, he signed to play at Stanford University.[11]