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Looking for a 400 yard shot

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Del the cat:

--- Quote from: willie on October 02, 2025, 03:38:35 pm ---
--- Quote from: Del the cat on October 02, 2025, 11:31:57 am ---
I've added more info and another pic to this blog post:-
https://bowyersdiary.blogspot.com/2025/09/wooden-flight-bow-arrows.html
Del

--- End quote ---

Thanks for  showing us more about your process.
looking at turkish flight arrows I see they were barrelled, I suppose to lighten the arrows where the stiffness was not needed on the outer thirds .
If stiffness in the center third can be accomplished by compressing the wood, one could "forge" an arrow of varying density by compressing a blank shaped like a long diamond.
in other words, an arrow of same diameter from end to end having lighter ends but stiffer midsection

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It's interesting that Harry Drake never worried about spine. I think stiffness is only really an issue if the arrow is flexing, and a decent shoot through bow correctly set up, with a mechanical (or flipper) release, shouldn't have much arrow flex.
It reminds me of some bloke on an archery forum telling me that spine mattered in crossbow bolts, I said it didn't, he tried to call me out, so I made a bolt with a paper tube shaft and shot it from a 50# bow pistol! It was fine!
If you can barrel and arrow to 5mm at each end, is it better if it is 5mm all the way along. I'm beginning to think that finding the optimum weight arrow for the bow (at minimum diameter) is the critical factor (that, and small wafer thin fletchings).
Obviously on an ELB (or warbow) barrelling to get the stiffness in the right place is vital as the arrow has to flex.
Del
(All just my opinion of course)

Badger:
   I agree Del, when the arrow needs to flex spine is critical, on a center shot bow there really is no need to flex. One thing that has always puzzled me is how critical the spine is on an atlatl dart. If they are too stiff, they just dive bomb.

willie:

--- Quote from: Badger on October 02, 2025, 04:44:46 pm ---   I agree Del, when the arrow needs to flex spine is critical, on a center shot bow there really is no need to flex. One thing that has always puzzled me is how critical the spine is on an atlatl dart. If they are too stiff, they just dive bomb.

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An atlatl dart that is too stiff needs to be thrown very hard to get going straight. The tail end of the dart needs to deflect easily because the nock is rotating  in a substantial arc due to the length of the throwing stick,  and if the dart is too stiff, it will rotate the entire dart around the fore and aft center of gravity. BTW, stiff darts tend to launch nose high, while it is a soft spined dart (or a dart that is thrown too hard), that dives towards the ground.


--- Quote ---It's interesting that Harry Drake never worried about spine.
--- End quote ---
could this mean that Harry never worried about measuring spine or tried to make adjustments to his arrows based on spine measurements? He must have had other more important criteria when making arrows ie. weight, length or diameter. I am guessing he still must have appreciated as much stiffness as the materiel would give, once the other criteria was met?

--- Quote ---If you can barrel and arrow to 5mm at each end, is it better if it is 5mm all the way along.
--- End quote ---
interesting question about whether a tapered/barreled arrow or a straight shaft makes much difference aerodynamically.  the maths of aerodynamics seem to be concerned with maximum diameter, at least with rockets and missles anyways as they seem to do well as cylinders
fuller diameters at the ends of arrows should make maintaining points and nocks easier tho, if not creating excess weight, but smaller max diameters in the mid section seem to be desirable for distance.

Selfbowman:
Just an opinion from a guy that’s still looking for a flight record. I have broadhead records. It could be that once the diameter being wider in the center reduces the drag on the back half of the the arrow. Increasing distance. I would draw a pic if I could draw. The increased drag is only in the center of the arrow where spine is needed. Just a thought.

sleek:

--- Quote from: Selfbowman on October 04, 2025, 12:44:01 pm ---Just an opinion from a guy that’s still looking for a flight record. I have broadhead records. It could be that once the diameter being wider in the center reduces the drag on the back half of the the arrow. Increasing distance. I would draw a pic if I could draw. The increased drag is only in the center of the arrow where spine is needed. Just a thought.

--- End quote ---

You are pretty well correct. The barrel shap creats what called a Coanda effect, named after the guy who would rather have discovered it any other way than how he did. Its a boundary layer that sticks to a curved surface as it flows over it. You have no doubt noticed it when washing the back side of a spoon in the sink. When the angle of attack gets too high you get boundary layer separation and that causes a stall. When an arrow wobbles it can cause the fail of the arrow to stall if the paradox gets too strong in increase drag. So you do want that curve in the shaft and as little paradox as you can get away with.

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