Mighty Mouse is right. Stiff spine wouldn't affect anything with your bow. You never mentioned what spine deflection your arrows are. I'd think .300's would be about perfect, but .250's would also be easily tunable too.I had my bow setup by my local shop when I bought it but was getting some erratic groups. I’ve just started bare shaft tuning to try to figure out what’s up and found 2 problems: bare shafts were hitting target angled downward (moved rest up 1/32” and they hit straight now), and left of my fletched shafts. The Easton guide says the second problem is a stiff spine and recommends a handful of remedies: decrease the spring tension in the rest, go down a size in arrow spine, turn up draw weight slightly, or add weight up front. I’ve already tried increasing my draw weight by ~5 lbs and no difference. My next move is to turn down the spring tension in my rest and/or add some weight up front on my arrows. I’d really like to avoid getting a weaker spined arrow if I can. Bare shafts hit about 3 inches left of fletched
Setup: Hoyt Ventum Pro 30, 65#/28.0” with Hamskea Hybrid Hunter.
Black Eagle renegades 27.0” with 12 grain wrap, 3 blazer vanes helical fletched and 125 gr field point. Arrow weight is 502 gr with 14% FOC.
Has anyone had any luck tweaking these variables to get a better result?