Essentially, it refers to the quality of arrow flight. From a poorly tuned bow, arrows will fly erratically, oscillating from side to side (fishtailing) or up and down (porpoising) excessively. In contrast, arrows shot from a well-tuned bow fly virtually straight.
Clean arrow flight has two positive results. First, it improves accuracy. It is true that a poorly tuned bow can shoot tight arrow groups–if shot from a machine or a machinelike archer. Unfortunately, even the best of us have slight shooting flaws, and erratic arrows magnify those flaws and destroy accuracy. Broadheads magnify shooting flaws even further. Thus, hunting accuracy is closely related to bow tuning.
Second, tuning affects penetration. An arrow that wobbles in flight will hit the target at an angle. Because the shaft does not follow directly behind the broadhead, it will drag against hiding, bone, and muscle as it enters the broadhead hole, wasting energy and impeding penetration. When an arrow from a well-tuned bow hits the target straight on, the shaft will follow directly behind the broadhead, virtually eliminating drag. Thus, a well-tuned bow assures the best penetration in big game.
Arrows in Flight
The easiest way to read arrow flight is to shoot through the paper. If you’re getting wild tears, say longer than two inches, consult an arrow-spine chart to make sure you have the right shafts for your bow. With the right arrows selected, set your nocking point and arrow rest so that a nocked arrow sits perpendicular to the string and in line with the center of the bow.
Remember this principle: If you’re shooting with fingers, tune for the front of the arrow. If you’re shooting with a release aid, tune for the back of the arrow.
When you shoot with fingers, ideally the arrow remains in contact with the rest only for the first six inches or so of its movement. It then oscillates horizontally out around the bow, never touching the arrow rest again. Thus, to affect the flight of a finger-shot arrow, you must influence the front of the arrow.
In contrast, an arrow shot with a release aid slides full-length along the rest. The tail (fletching) end of the arrow is the last section of the arrow in contact with the rest. Thus, to affect the flight of a release-shot arrow, you must influence the back of the arrow.
One other point should be made: When shot from a bow, all arrows oscillate to some degree. Finger-released arrows oscillate side to side (horizontally), and release-shot arrows oscillate up and down (vertically). Those facts dictate the style of arrow rest used for each style of shooting. Most finger shooters use a flipper/cushion plunger rest, which exerts the greatest control over the horizontal movement of the arrow. Most release-aid shooters use a shoot-through rest, which exerts greater control over vertical flexing of the arrow.
Adjusting Your Bow
With that background, follow these steps (for right-handed shooters):
Finger shooters: If the arrow tears through paper tail left, stiffen the cushion plunger on the arrow rest or move the arrow rest to the left. Both of these effectively move the point to the right in front of the tail which produces straight arrow flight. If the arrow flies tail right, do the opposite. If the arrow flies tail high, move the nocking point on the string down; if it flies tail low, move the nocking point up.
Release shooters: If the arrow tears through paper tail left, weaken the side plate of the arrow rest, or move the rest to the right (toward the handle of the bow). Both of these effectively move the tail to the right, in line with the point. If the arrow flies tail right, do the opposite. If the arrow flies tail high, try moving the nocking point down, although it may not have any effect. Weakening the vertical tension of the arrow rest should produce better results. With a two-prong rest like Golden Key-Futura’s TM Hunter, you would weaken the spring tension. On a rest with spring-steel support arms, like Golden Key’s Star Hunter, replace the arrow support arm with a more flexible feeler gauge.
Each one-pound increase in draw weight increases arrow speed by about two feet per second.
THE PAPER CHASE
Testing the straight and arrow
For paper testing, stretch a sheet of paper tightly over a frame and shoot through the paper to check your arrow’s flight. Several companies make paper-tuning frames, but you can make a simple frame by cutting a large window in a cardboard box and taping newspaper over the window.
POINT OF CONTACT
Beware the brush-off
Fletching contact may cause erratic arrow flight. To check this, spray the shaft and fletching with foot powder or deodorant (the kind that will stick to and make a smooth film on the shaft), shoot an arrow, and check for contact marks in the powder. Then turn the nocks on your arrows to eliminate contact with the rest. Some archers shoot feather fletching because feathers are more forgiving of contact, but if your bow and arrows are tuned well, you will get the good flight with plastic vanes.