I was wondering if anybody can help me. I shoot a Omen Pro @ 28.5 dl #70 dw and 100 gr tips, what would the proper spine need to be? I currently shoot Easton ACC Pro Hunting 300 cut to 26.75 inches. It stills seems to be too soft as i always get a left tear. What bothers me is the fact that I can see that the arrows fish-tail out to about 15 yds(the arrows are all slanted to the left in the target to that distance). Any distance after that the 4 NAP Speed Hunter are able to correct and control the flight. Groups are all great out to 90 yds but the first 15 yds really concern me. I have tuned many bows with great success and have always been able to get bullet holes. I could lower the draw weight or switch to a heavier arrow but I like the bow as it is.
It's how your bow is setup or tuned. You are probably getting contact or you need to add twist to your yoke, or your rest timing or center shot is off. or you could be torquing the bow a bit.
But it would be a pretty good bet that its not a spine issue.
No contact and I am tuning with a bare shaft. No matter what I do I always get a left tear. I can torque the bow or not and still get a left tear. Does not change if the rest is close to the riser or not.
I did some checking and the spine that you are shooting is actually a little to stiff. Easton's chart is shows that for your set up you should be shooting a 390 or 400 in the pro hunter series. A few times when tunning a setup with a drop away rest I have forgotten to have the **** vane up instead of down and had the same problem as you. I have a few different bows set up differently so sometimes I forget that with a drop away rest. Good luck with that.