i know exactly what you are going through. yes go heavier and stiffer and it should tune easy. it took me 5 weeks to admit i could not shoot 400 spine, was fixing to sling the katera. switched to 340 today and tuned it in no time. bh and fp are together and before i couldnt keep in in a 6 in circle. i had lots of 5575 arrows and wanted to use them. it caused me to loose a lot of sleep. this thing shoots great now.