Blume was recruited to Oregon State University by future Naismith Hall of Fame coach Ralph Miller. He was part of a 7 freshman recruiting class which joined 6 sophomores in making the 1977-78 OSU team the youngest in school history. Joining the 6'4" Blume on the 1977-78 OSU team was Rose City backcourt rival Mark Radford, at 6'3" another tall guard who would later spend time in the NBA. While Blume came off the bench during his freshman year, from the 1978-79 through the 1980-81 seasons, Blume and Radford would comprise a potent backcourt combination for OSU, helping take the team to the NCAA tournament during the pair's junior and senior seasons. The Beavers finished Blume's freshman campaign with a record of 16 wins and 11 losses, with the curly-haired freshman coming off the bench to see action in all but two games. Blume's place was an important one, averaging nearly 16 minutes of game time over the course of the year, during which he scored an average of 6.2 points and garnered better than a steal per game. The season was the first of four in succession for Blume during which he made at least 50% of his shots taken from the floor, finishing the year with a field goal percentage of.521. OSU showed some improvement during Blume's second year — a season in which he cracked the starting lineup for the opener. Blume's path to the starting five was paved by the decision of previous starter Brian Hilliard not to return to OSU to play his junior season owing to a nagging injury and loss of focus. Blume took the keys to the car and never looked back, finishing the season shooting.500 en route to a scoring average of 13.4 points per game, with his backcourt mate Radford putting up very comparable numbers. Together with 6'11 centerSteve Johnson, another future NBA talent, OSU was tapped for post-season play in the National Invitational Tournament, bowing out in the first round. The 1979-80 season was a breakout year for Oregon State men's basketball — with the team winning the Pac-10 title with an overall record of 26-4, topping out at #2 in the national polls, and gaining a regional 2-seed in the 48-team NCAA postseason tournament. The season also proved to be a break-out year for Ray Blume personally. During this first of two extremely successful seasons, Blume logged more than 1100 minutes of action, upping his scoring average to 15.4 points per game as well as his shooting percentage, which finally rested at.564. Blume added averages of 2.2 steals per game and 4.5 assists to his résumé, garnering national attention with 2nd team All-American honors. Ray Blume's senior campaign, 1980–81, is the legendary year of Ralph Miller's "Orange Express" — a season in which the team reeled off 26 consecutive victories, again winning the Pac-10 title with a record of 17-1, and sitting #1 in the polls for nearly 2 months. To the senior starting core of Blume, Radford, and Johnson were added two more future NBA players, small forward JC-transfer Lester Conner and highly touted Oregon-born freshman power forwardCharlie Sitton. Blume again combined shooting chops with defensive prowess, finishing the year with double-digit scoring on a much deeper team and upping his shooting percentage to a career high.569. He also managed to steal the ball 50 times for the third straight year and averaged 3.6 assists in Ralph Miller's old school "no bounce passes," backdoor-cutting offense. The dream season came to a bitter close, however, with the team dropping its home finale to Alton Lister, Fat Lever, and the potent Arizona State Sun Devils before a shocking first-round exit in the 1981 NCAA Division-I basketball tournament. A stellar defender as well as a dangerous perimeter shooter in the years before the 3 point basket, Blume amassed 205 steals in his 111 games as a Beaver, an average of better than 1.8 steals per contest. He finished his OSU career with a scoring average of 11.6 points per game. Blume was selected for the OSU Athletics Hall of Fame in 2004 and named to the Pac-12 Basketball Hall of Honor in 2017.
Professional career
Blume was selected by the Indiana Pacers in the 2nd round of the 1981 NBA Draft and traded immediately to the Chicago Bulls along with a future 2nd round pick in exchange for Mike Oliver. Blume played for the Bulls during the 1981-82 season, appearing in 49 games, starting twice. During his brief stint in the association, Blume scored 4.6 points per game during an average of just over 11 minutes of action. Blume was sold by the Bulls to the NBA's San Diego Clippers on October 8, 1982 but he never saw regular season game action with the team. Blume was waived by the club on October 28, 1982. After his short NBA career was over, Blume played basketball professionally in Europe.
Life after basketball
Following his professional basketball career, Blume returned to Portland, Oregon and began a lengthy career in the public sector working for the Multnomah County Roads Department.