I am shooting a CD WF 25x with 38# UUkha limbs. My previous arrows were 500 spine, 30 inches with 120 grain points and flew very well. I was looking to see the impact of small diameter shafts, so I purchased identical arrows, except that they were 3.2mm shafts. These arrows are flying extremely weak and it seems like the adjustments I am making such are decreasing poundage, adjusting center shot etc. are making the problem worse. Any advice?