A friend is shooting an '05 Rapture at 60# and 27". He is shooting 26" GT XT 3555s with 100 grain heads and 4" vanes at 254fps. I am not sure of his arrow weight. But he has one of those God-awful giant peeps with the amber lens and an alignment tube. Once he loses that he will get a few more feet per second, I am sure. Your nubers seem odd, though, because the first arrow was so much faster and it shouldn't have been. Only weight is the issue, not spine.