I think dynatec is on to something. Carbon arrows will lose spine, over time. I noticed this with Easton Red Lines. After shooting awhile, my groups opened up. Especially as I moved back, or shot broadheads. I also shoot fixed blades (Stingers and Slick Trick). I think the constant pounding into a target and beating a bow puts on an arrow contribute to this break down. I'm not downing Easton arrows, but the Axis arrows had this problem when first brought out. This may well be corrected now. Not knowing how long the arrows are, or how heavy a broadhead you're using, I can't say positively but, you may need a stiffer arrow, also. Re: your Allegiance, it is vitally important to set nock point level.