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Bow Tuning

Centre-Shot | Bracing Height | Limb Tiller | Stabilisation and Damping
Nocking Point | Button | The Walkback Test

When you have shot for a while and are (hopefully) shooting quite well, then you ought to think about the more advanced set up of your bow and tuning it in properly. Although gadgets are no remedy for bad shooting, having a well tuned bow will make shooting it feel nicer and add some points to your score, especially outside.

This is a measure of where the arrow points in the first place. Nock the arrow and hold the bow out in front of you, looking down the arrow. Line up the string with the centre of the bow and see where the arrow is in relation to the string. For right-handed archers, the point of the arrow should be seen to the left of the string. This is the most widely recognised compensation for using a finger-release. Of course, this works the other way round for a lefty.
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Bracing Height
The distance from the nocking point to the arrow rest. When you bought the bow, you were probably told amongst the mountain of new information, the right bracing height. If you can't remember what it was, a basic guide for a 68" bow is somewhere around 8 to 9 inches. If you can, hunt down the manufacturer (with your internet/phone, not your bow!) and see what they recommend for the model you have. Other people in the club may also be able to help you. There are usually about 2 or 3 bracing heights that suit the bow well inside the range sepcified for it, like resonant frequencies, but in these cases they damp the bow better than any other lengths. It is best experimenting, and when you get confident you might find it works better outside these limits. One point of note is this, a longer bracing height will give a shorter power stroke for the same distance pulled back because it reaches this length faster than a short one. Also, a longer bracing height means that more energy has been wasted holding the limbs bent permanently, when it could be imparted onto your arrow. Therefore a lower bracing height would seem the way, but too far and the limbs will probably not be synchronised properly, making the shot 'unclean'. You can measure you're bracing height using a bracing-height gauge, and lengthen it by adding twists into the string.
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Limb Tiller
Because modern target archery uses three fingers, one above, two below, it means that the bottom limb is usually put under more stress than the top one. Most manufacturers allow for this with a little positive tiller built into their bows to compensate for this. What's positive tiller? Well, quite simply, the top limb needs to be under the same force as the bottom one at release, othrewise they will not both snap forward at the same speed and at the same time, resulting in a messy shot. If you are able to adjust your limbs or are worried about the tiller you currently have, then the basic rule of thumb is that the distance from the base (the bit at the riser) of the top limb to the string should be a little more than the distance from the base of the bottom limb to the string, about a cm. Again, it is worth experimenting with what feels right and produces a smooth shot.
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Stabilisation and Damping
Modern target bows benefit from stabilisation and damping. Firstly, the long-rod. Like most things in archery, you need one that suits your bow, this is important, try it out first at a shop, try lots out, try lots of combinations of V-bars, doinkers, the lot, so you know what feels right for you. The main point of note is that a long-rod's primary purpose is to put some weight outside the bow to help in the balance of it, not, as many think, as stabilisation, although it does that too. Most people start with a long-rod, but this often causes the bow to fall forward alarmingly, so one can also put on some V-bars to bring some weight back towards the archer. This is often used by a lot of people as it provides a good firm bow in the hand that's well balanced. Again, make sure you try before you buy, and if they're adjustable, then play about with what they do, but most importantly, ONLY CHANGE ONE VARIABLE AT A TIME AND NOTE WHAT YOU DID!!!, otherwise you won't be able to recreate that 'magic' shot when everything felt right with the bow.

More recently, people have started putting rubber onto their bows, these take 2 main forms, the limb-saver and the doinker:

Limb Savers
Pieces of rubber, mushroom-like in appearance, which one sticks to one's limbs. Opinion is divided about these, some say they're awful and slow the bow down, some people love them. One thing is without doubt, they DO absorb a lot of vibration from the bow. The other point of slowing the limbs down is, in my opinion, rubbish. I use limb-savers and when I went to Quicks in Waterlooville, they stuck them on and to prove this point had me fire through a metal ring which measures the speed of the arrow before and after they were applied. The results were identical. This is down to where on the limb they are placed. Naturally, the further along the limb they go, the more vibration they will absorb, but too far and they WILL slow the limb down. The secret is to have them at the fade-out of the limb, the part where it only starts bending. This is best described as the point where the wood/carbon/whatever which attaches to the riser comes down to a long V-shape (when looking at the narrow edge of the limb). Where this 'V' meets is the fade-out as the limb starts bending there. This is where the limb-saver should go, ideally.

Pieces or rubber that attach to the bow or stabilisation equipment to damp the shot. There's probably little scientific reasoning behing these (I can't be bothered to think about it), other than they seem to work. If added to the end of a long-rod, then the vibration taken along the rod is absorbed by the doinker and not reflected back down the rod for you to feel as you loose the arrow. Also, they can be fitted direct to the bow with weights on them to fine-tune the feel of the bow and to absorb vibration from the bow. Many people have found that these do help getting smooth shots out and their adoption has been more widespread than limb-savers. Golden-rule time, try one, you might not need it, it might make all the difference, but don't get something because it looks nice, get it because it does the job you want it to.
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Nocking Point
Very Basic
Hang on a minute. Do you have a nocking point on your string? If there isn't one then you need to fix one (a bit of sticky tape works well as a temporary device) to your string. Find the spot on the string which is parallel to the arrow rest and move up by half a centimeter and fix the point there. This will not be accurate but will serve as a temporary point.

To get the most from your bow you need to set it up correctly to enable a smoother and more accurate flight of the arrow. One part of this setting up is aligning your nocking point and should only be done when you can group your shots. Take several straight arrows and remove the fletchings from one. Shoot all the arrows into the target noting where the unfletched arrow lies compared to the others. Do this several times until you are sure that the unfletched arrow always goes in the same place away from the others. If the unfletched arrow goes higher than the others then lower your nocking point, but if it goes lower then raise it (you only need to raise and lower by a few millimeters usually). Change the nocking point and repeat the process until they all hit the same spot (with perhaps the unfletched one slightly lower and to the left of the fletched ones). The idea behind this is that if the fletched arrows leave the bow at an angle then the air resistance against the fletchings will pull the arrow until it is flying straight. However the unfletched arrow will not be subject to this air resistance so will continue at the angle. If the nocking point is low, then the unfletched arrow will fly upwards, higher than the others. A new and different set of arrows means you have to adjust the nocking point.
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The Button should first of all be inserted into the bow so that the arrow is aligned as described in centre-shot, above, and so that it is in contact with the middle of the arrow when the arrow is nocked and on the rest. When you become proficient enough to use a button, this too needs to be tuned before it works to its full capacity. Again shoot several fletched and one unfletched arrows several times noting where the unfletched arrow lies. If it is to the left of the fletched (for for a right-handed bow) then the button spring needs to be softened and if it is to the right then the button spring needs to be stiffened. Even though you have aligned the arrows to centre-shot, you still need to play about with the spring and this is done outdoors with the walkback test.
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The Walkback Test
Do this test after you have set up the nocking point.

When you are outside set up a boss at about 40m and pin a small piece of paper near the top of the boss to aim at. Set your sight mark for about 20 metres. Stand about 5 metres away from the boss (10 if you are using carbon arrows) and shoot about 3 arrows into the target. Mark down where they group. Now stand 10 metres back from the target (15 for carbon) and shoot another 3, noting where the group lands. Repeat this process of stepping back an extra 5 metres and shooting three arrows until the arrows land at the bottom of the boss. (Note you shoot three arrows to eliminate bad looses). At the end you should have about 6 different groups starting from the top of the boss going to the bottom. If they are in a straight line then your button is tuned properly. If they slant to the right at the bottom like this \ then you need to increase your spring tension. If they slant to the left / then you need to decrease the tension. If there is a C shape then you need to move the whole button into the bow. If the C shape is facing the other way like this ), move the button out of the bow.

It it worth noting that if you have two sets of arrows, eg carbon and aluminium, then it is an idea to have a separate buttons for each set if you can afford it. That way you know that both are always tuned properly to the bow.
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If you think you've got your bow nicely tuned, but you just can't get the scores you want, maybe you need to take a look at the how to shoot page.
My little Disclaimer
This page has got loads of handy tips and tricks, but if you try something and then Gary or Chris have a go at you, please don't blame me. Pleeease. It's not my fault really. I don't know anything.
big and powerful site disclaimer »
(See article v)