I have know idea howmany GPI my arrow is. I shoot a 22/16 XX75 tipped with a 125 grain 3 blade snuffer broadhead. I'vegotta get my stuff together next year and learn more about my arrows. I've been bow hunting for 21 years, when i first started shooting compounds i started out with 19/16 XX75's and as i increasedmy draw weight i went to a 21/17 XX75. Afterswitching to a recurve 10 years agoand uping my pounds in the low 70's i shoot 22/16 XX75with a 125 grain 3 blade snuffer. My arrows fly good for the most part, i'm guessing i could probably be shooting a lighter arrow. Wish i knew more about arrows and weights!