Chapter 4: Know Your Bow and Arrow
Matching Arrows With Your Bow
Arrows must be matched with your bow. Mismatched arrows may not fly correctly or accurately. Good arrow flight can be obtained if the balance point on a completed arrow (a fletched arrow with the point attached) is located 10-16% of the distance forward from the center of the arrow toward the point. Arrows that are too lightweight for your bow may cause you to essentially “dry fire” your bow.
Spine and “Archer’s Paradox”
Every arrow shaft has a degree of stiffness called spine, which is its resistance
to bending. Bending, known as “archer’s paradox,” occurs
when an arrow is released from the bow. The forward thrust of the string causes
the shaft to bend in one direction and then react in the opposite direction
as it speeds downrange.
Spine strength must be matched to bow draw weight. If your arrows are too
lightly or heavily spined for your bow, the “archer’s paradox” movements
will be extreme, resulting in poor arrow flight and loss of accuracy. (It’s
better to err on the stiff—too heavily spined—side.) Arrow manufacturers
publish selection charts that match bow weights to proper arrow spine. Your
local archery shop will help you match your gear.
If the bowstring hits your arm regularly when you release, check your wrist and elbow position in relation to the bowstring. In addition, the bow’s draw length may be too long, or you may be gripping the bow incorrectly.
Arrow Shaft Length and Labeling
Arrow shaft length also must be matched to your bow. Drawing an arrow that’s
too short is dangerous because it may slip off the bow, while an arrow that’s
too long adds unnecessary weight and weakens the spine of the arrow. Arrow tables can help you make the right selection.
Aluminum arrows are labeled by their outside diameter and the wall thickness of the shaft.
For example, if an arrow is labeled 2013, the arrow has a 20/64-inch outside
diameter and a 13/1000-inch-thick shaft wall. A thicker shaft provides greater
Aluminum and carbon-fiber combination arrows are measured by spine deflection. The smaller the number, the stiffer the spine. For example, 3-60/340 means three wraps of carbon-fiber, with an aluminum core tube diameter of 60, and a spine stiffness rating of 340.