What would be the most likely cause of this. I just had new strings and cables put onmy bow, tuned perfectly, (by a guy with the exact same setup). My field tips are flying great but when I put on bhs they start nose-diving out past 25-30yds. I am trying to shoot wac ems but also tried several other types and they all did the same thing. I have been consentrating so hard that I believe my form and shot sequence has never been better. At 20 yds they are pretty close to bullseye but they drop about 4-5 in at 30 yds and 7-8 in at 40 yds. The arrows also seem to move up and down when flying. I'm shooting around 260 fps with a 420 gr gold tip 7595. like I said I'm busting nocks with field tips. Also the wac-ems dove the least. thanks.