Bare shaft tuning

[Tartar Horde]

Thanks SS, we are talking about having your arrows matched/tuned to your Bow, this allows your Bow to impart the greatest amount of energy into your arrow without the arrow becoming unstable. When we talk about "spine" it means the amount an arrow bends as it leaves the string, stiffer spine means the arrows bends less, weaker spine more. The arrow has to bend just the right amount to clear the handle, no more no less, anything outside this range means your arrows are not performing as they should and this will effect accuracy and arrow speed. You want your arrows to fly as smoothly as possible for obvious reasons.
Here's a slow mo video of a correctly spined arrow. https://www.youtube.com/watch?v=cP8XVW4H90g

Here's a video of a poorly spined arrow too stiff, watch how the arrow starts to fly with the Nock (back end) pointing right. It will continue to fly like this to the target. https://www.youtube.com/watch?v=aeL4xes384M