Our friend,
denverjayhawk, over on Rock Chalk Talk had an extensive interview with Castor when he originally committed to Kansas. It is definitely worth your read. Here is a piece of the interview where Castor talks about his kickoffs and field goal ability:
My kickoffs have really increased this year in both hang times and distance. This summer I had numerous kickoffs that were 70+ yards with hang times around 4.5-4.75 seconds.
My field goal distance also increased during the off-season into the summer. In May of this year I was able to kick a 65 yard field goal in practice and I also managed to hit the crossbar at 70 yards, but couldnt quite make it.
According to the interview, Castor said his in-game long field goal was 53 yards.
According to the Denver Post, before the state semi-finals, Castor was 14 of 24 on field goal attempts for the year but a few of those misses were due to the coaching staff giving him chances to kick from 69 yards because misses at the high school level means the opposition starts from the 20 yard line, not from the spot of the miss. He also averaged 42 yards a punt his senior season.