Alan Case's flight arrows - learning how to make them!

[mikekeswick]

Ok so I actually got to shoot my new arrows the other day.
The wind was still quite gusty especially up a hundred feet or so.
As I said earlier these arrows vary from 190 grains to 308 grains. The best performer was consistently one that weighed 231 grains. Best distance with this arrow was around 335 - 350 yards. The rest were all around the 300yard mark.
Now I can't wait to get my proper flight bows ready. This bow is a light weight Turkish warbow design (55#@28) and therefore isn't suited to ultra light arrows. After looking at a bit of video I shot it also appears that i'm only drawing 27 max...pretty scary to draw these knitting needles right back That will come with more practise though. The arrows are all 28 inches long as well. The bows limbs are covered in leather which hurts the performance a little. This bow is 48 inches long (too long!) and the limb cores are hornbeam not hard maple. It's meant to be durable not a rocket ship!
So all in all I think the arrows went pretty well and I can make them better next time. I have some quality Tonkin poles coming now.
Shorter, heavier flight bow, shorter arrows and a siper (overdraw) should see me past 400yds at least

[joachimM]

That's a really good result if you ask me!
To get around 350 yards you'd need an initial arrow speed of about 220-225 fps according to my guesstimations. Did you chrono the arrows or do you want to avoid blasting them to pieces on a target (well surely you want to avoid that...)? 
I've also found that precise nock placement of the arrow on the string makes a considerable difference in arrow flight.
My difficulty in drawing is to combine a snap draw with a release during the backward motion of my arrow hand while avoiding a short draw. And shooting at exactly the right angle (was it 43°?).
Don't know how you guys determine the right angle, but that's about my biggest challenge, as now it's just a gut feeling.

As far arrow tuning and seeing how it flies, you don't necessarily need a 400 m range. To test them I shoot them vertically (actually, at a slight angle) and check if they kick sideways. Most of the time, they land within 50 m of me. I might want to wear a helmet as I they get lost out of sight when they fly well :-)

[Badger]

  Great results!

[mikekeswick]

Joachim - Yes you are right I wouldn't dare shoot them through the chrono as they would probably end up going through the chrono...haha! I have shot some heavier arrows of around 360 grains and I was getting about 210 -215fps (from memory?). This is with a B50 overbuilt string. Adam Karpowzi has written in his 2nd Edition book that he has been experimenting with fastflight on lighter hornbows and they seem to be useable. I am too scared to try one on this bow as I am pretty attached to it....
Angle...I just guess! It would be worth videoing to see exactly what angle you shoot at. As for drawlength you could try wrapping some tape around a longer shaft at your intended drawlength so that as you draw you feel the tape to confirm you have fully drawn the bow.
Badger - Thanks! More to come!

[avcase]

Good shooting!  You are getting into that zone where the arrow disappears into the sky.   It is fun following your progress with this. 28" is really long for a split cane flight arrow. I don't think I could make split cane arrows that long and light without losing spine.  Or, I'd have to use a very long taper to a tiny point, but this shape doesn't fly far for me. A 23" arrow with an overdraw is about perfect for a 27" draw length.

A few degrees high or low doesn't make a huge difference compared to other factors.

B50 is worst case performance wise, but I can understand the caution with something you put so much work into.

Alan

[mikekeswick]

Yes the 28 inch arrows are a bit long!
I am now working on making a siper and learning how to use it.
I'm looking forward to getting some better quality cane and making some dedicated shorties.
To get the weight down on these arrows I had to go silly thin on the walls...so much so that I don't have much confidence in the lightest arrows strength. Obviously going shorter will help but I was wondering if you had made any of these arrows with narrower (width) sections to give thicker walls but smaller overall diameter. I think I will try that on my next ones. Greater sectional density should help. My lightest arrow has plenty of 'space' inside!

[avcase]

The stiffness of the arrow is primarily driven by the outer diameter. The stiffness of a solid section increases 8 times if the diameter is doubled, so just a small difference in diameter makes a large difference in stiffness.

Thicker walls for a hollow arrow doesn't make as large difference to stiffness, but it does add a lot of mass.

For example:
Arrow 1, solid Tonkin arrow shaft, 28" long and .25" outer diameter:
Mass = 412gr , spine = 38.8#

Arrow 2, 28" long, .25" outer diameter and .125" hollow inner diameter:
Mass = 309gr, spine = 36.4#

Arrow 3, 28" long .25" outer diameter and .177" hollow inner diameter:
Mass = 205gr, spine = 29.1#

Arrow 4, 28" long, .267" outer diameter and .186" hollow inner diameter:
Mass = 242gr, spine = 38.6#



Alan

[joachimM]

Once you have the properties of the materials you're working with (a baseline diameter and spine is enough) you can calculate the expected spine of thicker or thinner arrows (with same wall thickness), at least in principle. I do this for bow thickness and draw weight, and it works pretty well for me.

You can use the excel sheet below (bow thickness tab, but should work as well for arrows).
With or without the hollow 0.125" diameter on a 0.25" thick arrow would only make a spine difference of c. 3.5#

[mikekeswick]

Thanks for those numbers Alan. That has saved me quite some time testing. When you think about it it makes sense.
It might be a week or so before I can get started on my next 'batch' of arrows but i'm looking forward to getting some new ones made. I'll make some of those candycanes you mentioned before as well. I have some suitable pieces of purpleheart and hornbeam
In the mean time I think i'm going to cut a few inches off the front of the arrows I've already made, both to stiffen/lighten them and give me a bit more room to make better points. I have a friend who will turn me some brass points on his lathe.