Spikeer is right. I pulled a lot of hair out over this issue a couple years ago with my 2008 FireCat. First I lined the rest up using a laser and it would not tune. Then I just eyeballed it and set the centershot in line with the cam grooves (left of physicl center of the bow) and I remember it being about 1 1/16". The bow shot terribly. It wouldn't bare shaft or paper tune. Si I just gave up and set it for 13/16" and shot the bow. Being as I don't hunt anymore trying to tune for broadheads isn't and issue. I did get the bow shooting decent though.
Then I got a 2010 Alien Z and then a 2011 Nemisis. Same issues as before so I just set the centershot for best arrow flight and grouping and let it go at that. Both bows shoot wonderfully with the rest somewhere inside center.
Now FYI I do not grip a bow so hand torque shouldn't be the problem. I also tried about nine different rests, blades and drop aways with similar results. I differen spined arrows, 600 spine all the way to a 300 spine and they all act the same. Moved the rests over a span greater than 1/2". Nothing changed. Luckily I know ABOUT where to set a rest initially so that's what I do. Then I shoot the bow and don't worry about it.
It's just like usng a chronograph to check everything. Tune and supertune a bow all you want and keep checking the speeds. A certain bow set up for a certain arrow at a given draw length and draw weight is only going to produce a certain amount of speed. Set it up, tune it, and shoot it while forgetting those things that get so frustrating.
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Martin/Rytera Staff Shooter
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