Yes, they are both totally different...
BPF 1.15 is a measurement used for bats NOT legal for High School or Collegiate play (Little League and Senior League Bats):
Non-wood bats used in divisions of play Little League (Majors) and below must be printed with a BPF (bat performance factor) rating of 1.15 or less.
BPF (Bat Performance Factor) is simply the increase in the liveliness of a ball hitting a bat compared to throwing a ball against a solid wall (i.e., 20% faster rebound = a BPF of 1.20).
BBCOR .50 is a measurement used for bats that ARE LEGAL for High School or Collegiate play (- 3 drop bats primarily)...
Here's a link that can explain BBCOR in depth much better than I can:
http://baseballexpress.wordpress.com/ncaa-bat-ban