Monday, 8 April 2013


I don't usually worry too much about arrows, but I've recently been discussing distance, not actual flight shooting but reaching the 180 yard clout mark.
One problem is that archers are a bit like fishermen in so far as they will have an optimistic view of how far their bow shoot or how big their fish is. Of course measuring distances is trickier than weighing a fish.
This line of though came about for a couple of reasons that happened to coincide.
Firstly a chap I made a bow (60# 175fps Yew longbow) for a year two ago said he had difficulty making the clout distance and was generally 10 -15 yards short. The other thing was shooting the big bow the other week where there was 30 yards discrepancy between some shots.
I Emailed my thoughts to one of my web friends Mike Roberts of Robertsbows he makes some blisteringly fast bows and recently posted a self bow which achieved over 200fps. He's also made Asiatic style bows with horn and sinew so he knows his stuff.
Anyway he agreed that 175fps should get to 180 yards with no problem shooting the right arrows.

I've set about making an experimental arrow to test in one of my bows which shoots my 'standard' arrow at about 175fps.
My guess is the factors leading to short distance are .
1. Arrow too long.
2. Fletchings too big (Thread binding on fletchings is a bad thing for drag).
3. Drawing short. Most people I've seen tend to overestimate their draw length, often by an inch and sometimes by nearer 3 !
4. Holding at full draw/poor loose.

I didn't want to get into actual 'flight arrows' as such, but I wanted to try some sensible tweaks.
I have some bamboo shafts which are spined 45-50 which is 5lb stiffer than my standard, they are about 5/16" at the fat end but considerably slimmer at the other. I didn't want to go silly with weight reduction but I've gone smaller on the fletchings.
Unfortunately it will be a while before I can test the arrow as I'll be at a field shoot next week and I need to get up the club to have some room to try it.
I have made a similar arrow before to try from my Asiatic style bow (Fibreglass/Maple, it's on the website I think) ... Of course I lost it, there's not much room at the club and it sailed off into the woods.

The ideal arrow shape is barrelled for minimum aerodynamic drag, minimum weight whilst keeping sufficient stiffness. I couldn't be bothered to barrel an arrow, but the bamboo with fat end to the point seemed like a good compromise. One of the guys at the club opined that bamboo doesn't make good clout arrows, but we'll see.

My standard arrow weights 389 grains, the bamboo one was going to be about 50 grains lighter so I added a 1.5" length of coat hanger glued down the hole at the front end, this also helps to bring the centre of gravity forward a tad as it was a bit near the geometric centre. It then weighed at 373 grains.
I used my little model makers lathe to turn a point out of antler. the lathe struggles with steel, but the antler machined beautifully.
You can see the point end is similar thickness to the standard but is hopefully more aerodynamic. The flights are much lower profile and shorter (2.5" as against 3") and the nock had been faired in to a smoother profile.

Just to clarify a bit. I can measure arrow speed in my garage shooting through my chronometer, however actual distance requires somewhere safe to shoot and is dependent on many factors other than simply speed.
As an example consider a golf ball and a ping pong ball, they are similar in size but vastly different weight.
Our experience of the real world tells us that if both are launched at 100mph the golf ball will go further than the ping pong ball. Our experience also tells us that we would rather get hit by the ping pong ball. This shows that reducing the projectile weight isn't necessarily a good thing. It's about matching the arrow to the bow to maximise the performance.

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