3 4" feathers weigh in at about 6-8 grains, 3 2" Blazers weigh in at around 13-15 grains. The difference is minute but straight out of the bow, theoretically you'll be a fps or two up with feathers over Blazers, down range, I simply don't know, haven't played with my chrono out to distances with feathers. I have no desire to shoot them anymore so I don't tinker with them either. If I didn't make up arrows for friends, I wouldn't have gotten a chance to weigh them out either.