Dude your math is so far off..
C=pi * d, but d is not d of handle'a rotary motion, but rather the spool! The length of the handle has nothing to do with length per turn! You could put a 100ft long handle on a 30 ipt reel, and it will always be 30 ipt. Or you could put a 5 mm handle on it and it would still be 30 ipt.
No offense tho. It is a common misconception.