I'm having a problem with my arrow flight beyond 20 yards!! Arrow looks to be flying good from 20yds and in but then beyond 20 yds it looks as if the nock end is corkscrewing to the target!! What would be the most likely cause of this?? And best solution?? I know it's difficult to troubleshoot w/o seeing the arrows fly but has anyone solved this problem before?? Here is my current setup:
Bowtech ext vft 65lbs, 27.5 in. draw.
Goldtip XT 5575 @ 28 1/4 in. 369 grain arrow
85 grain points, 3 7/8 in vanes
Whisker Biscuit B2 rest

My calculations put that at an FOC of about 7.6%

I forgot to mention that the arrow flight I described is with field points. I know I'm losing energy as the drop in my arrow from 20-25 yds is 6+ inches!! I'm currently trying all of the prescribed fix-its in my tuning guide but to no avail as of yet!! Let me know if you have any insight!! Thanks!!