# Natural arrow spin direction



## Frogslayer

So this might be a dumb question, but I’m asking it anyway. 
Someone told me that there was a way to determine the natural direction on an arrows spin when shot from your bow (left vs right). They said you would do this to know which helical or direction of offset to put on your fletching. The reasoning behind this was to keep the fletching and arrow frm fighting each other. 
So is there a way to do this and if so how?


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## EAvila

I'll be the first to admit I'm totally ignorant when it comes to this, but what would impart a spin on the arrow if not the fletching?
Unless your string could do this, there's nothing else that would do it and as far as I know all physics rules would still apply.
(ignoring the spin of the earth and any other forces that would be irrelevant) There is no inherent "natural" spin that I can imagine.

Adding the spin via offset fletching is to increase accuracy as a rifled barrel does to a bullet.


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## GRIMWALD

The following video should answer most if not all of your questions.

https://m.youtube.com/watch?v=kV0npx2rWxQ


GRIM


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## Arrowninja

I index the top of my nock on a bare shaft with a sharpie, then start with shooting a target approx 6' away with a few arrows and check whether I get a consistent clockwise or counter clockwise rotation. Then back up a few more feet and see if I still get the same rotation. 

My PSE Supra target bow spins left, while my PSE Evolve 31 hunting bow spins right. After learning this, I re-fletched all my target arrows to a left hand fletch and WOW, I was surprised how tight my groups became from that change. 

Both bows are RH, I was shooting factory strings, and using a RH offset fletch on all my arrows before learning this. I'm guessing my arrows were coming out of the target bow LH then had to stop from the RH offset, then start spinning RH. 

Good luck with this and tight groups!


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## Frogslayer

Thanks guys, I’m going to check mine out. I might have to buy a left clamp for my jig.


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## Bowgren2

Levi Morgan's "Choosing the Right Vanes for the Job" mentions that 99% of use do not check the natural launch rotation of the bow. He uses a bare shaft (no vanes) and marks the top with a silver or white marker. Stand about 2 yards from the target and shoot. This shows how the arrow spins off the bow. He claims the arrow will stop spinning that way as the vane takes over causing a loss of guidance during that time. The article is about improving accuracy over longer distances (past 60 yards).


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## Frogslayer

So I tested my target arrows nvx23 and got right turn. I shot my 5mm 3dhv and got left turn. Both shot from same bow. How odd is that ?


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## GRIMWALD

LOL!!!!!
This is not a new subject, I first tested for rotation as much as twenty years ago.
I found I could control the rotation of the shaft by changing the direction of my string twist.
Now with a better understanding of arrow spine and how placement of the spine can change bow tuning results. It could be as simple as, with one of your arrows, the shaft oscillation is causing them to rotate in one direction and in an other direction with the others
Maybe the first bend is into the bow for one group and for the second the first oscillation is away from the bow causing a different spin direction.


GRIM


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## Frogslayer

That makes sense. Still have to buy a new clamp


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