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 10 to 16 percent of the arrow’s total weight with point attached is in the forward half of the arrow. 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 means 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.

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. Spine strength must be matched to the bow’s draw weight to minimize arrow flexing during flight. Arrow tables can help you make the right selection.

Aluminum arrows are labeled by their outside diameter and the shaft's wall thickness. 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 stiffness.

Internal component carbon 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, an aluminum core tube diameter of 60, and a spine stiffness rating of 340.