I had a bow that just would not seem to tune and the problem ended up being the limbdriver. There are two allen screws (set screws). One locks the launcher arm on tha shaft and the other locks the string arm on the shaft. First, the launcher arm set screw came loose and that housing worked its way down the shaft. It seemed like it would move to the right on the draw and, as the arrow launched it would go left. I snugged that one back up against the body of the rest and tightened it down. The bow tuned up and shot great for about 3 days and then it started again. This time the problem was the loose set screw on the string arm. Same problem, it slid down the shaft (to the right this time) some and the rest would have a sideways movement. It may be a long shot but I would check those screws and make sure both arms are snug up against the body of the rest.

Thank you for the suggestion. Funny you mention that as the exact same thing happened with my brother 2 years ago. We were about to throw his bow in the trash and one of the set screws got so loose the launcher arm actually came off. We tightend the rest and fixed the problem. I checked all the screws on the rest, cams, etc tonight. Nothing loose.

When you lowered the poundage,did you redo the walk back?

It still sounds like a spine issue but you should be able to see results with the adjustments you have made.Might be time to try and go the opposite way of the book.Try opposite adjustments from what you think they should be.You most likely have past the point of being too far.


Also,double check the rest as Bruce states.Check for lean,anything that could cause a problem.

Yea,it is one thing to tune a bow like a target setup and get her tuned in and shooting lights out but a completely different game to screw on broadheads and get them dialed in.

Heck,AA calls for a stiffer spine than OT2,especially the way I do it.(always give atleast 1" overdraw,and usually take a little off of ibo speeds for a rotating module when below 30"))My arrows are dead center in the green for a perfect spine match and there is only 1 spot on my rest when fieldpoints and broadheads impact the same at 40 yards but I can get bareshafts to hit with fletched at 20.:s13:

In the process or walk back at 64#. I'm beginning to think it may be an issue with me, form, and this bow if that is possible.

I now know why you don't trust a laser. Before I started this am I measured the rest. After all of the movement the V in the rest was only at 7/8's from the riser. Pretty close to where center shot would be. Considering how much I've moved it, wasn't even close when I started. So I'm at 7/8's and I have no windage adjustment left in my site. That doesn't seem right.

I just eyed the bow and set the rest. Measured and is 3/4 from the riser. That is where I am now and starting the walk back.

Just to make sure,you are doing the walk back with field points?


You sight should not be out of windage with the rest at 7/8",that seems odd.

Correct.

Well it shoots fine at 64#. Walk back was right on with me eying it. Shot broadheads at 20,30,40 and right in the circle. bare shafts within an inch of fletched.

One of three things. Spine issue, I'm torquing the bow at the higher poundage or the centershot was so far off to start that I went past where I needed to be so was getting no correction.

Going to tighten it back down later today and see what it does with current rest setting. If It still won't shoot I'll just shoot it at 64#.

I'm wondering if I went past centershot. Last night, prior to moving my rest it was doing the same thing at 64#. Nothing changed until I moved the rest back in toward the riser today.

Sometimes you can go past the point of no return and your adjustments at that point will be opposite of what they should be.I have run into this a couple times broadhead tuning.

There are many factors that can come into play when tuning and you touched on a few of them at once it seems.That is when it gets tough.