Thread: Arrow spine

My personal approach is (albeit I shoot 50, 55 and 60lb recurve and hybrid longbows) is:

- Buy full-length (32") GoldTip (Hunters or Hunter XT) shafts suitable *or slightly too stiff* for the weight I'm pulling
- Determine the point weight I want to achieve at least 18% FOC and an arrow weight over 500grains (momentum trumps kinetic energy when bowhunting)
- Cut 1.5" off the end, resulting in an arrow still longer than I need
- Square the cut end, put in insert and point (say, 100grain insert and 200grain point)
- Put in nock
- Mark a point on the ground 10m away from my target
- Shoot the bare shaft at a point on that target, with my best form, with my bow exactly above this mark. Shoot 10x shots
- Look at angle the shaft sticks out from target: nock will be angled left, indicating dynamic spine of shaft is too weak
- Remove nock, cut off 1/4" from nock end this time. Square the cut, and put nock back in
- Repeat 10x shots and keep cutting back until the the nock is dead straight, aligned with the point in relation to my ground mark
- Now, walk back 5m, and repeat. Fine tune the cuts this time down to 1/8", as needed, until the arrow flies true.
- Walk back finally to 20m, and ensure the same.

If the arrow flies absolutely true at 20m, I have all bow energy going into that shaft, and am now ready to fletch. I have the perfect arrow for that bow, and I don't need to paper tune, or bare-shaft tune against fletched shafts. The point of bare-shaft tuning is that you see how the arrow really flies, without all the compensation and 'guidance' smoothing over poor form and dynamic spine issues. Very revealing! In fact I find it so revealing that I always keep a bare shaft in my quiver, to see how much my form sucks, or doesn't suck. A bonus too is that your broadheads (which are basically wings on the front of the arrow, fighting with the flights at the back) will tend to shoot like points once your arrow is properly tuned.

Works great. Plenty of good videos on YT about the benefits of bare-shaft tuning. Clay Hayes, especially good.

YMMV!