It is important you use your bow’s peak draw weight (heaviest part of draw cycle), not let-off. Bow Poundage – Next you will need to know your bow’s poundage.In general, the longer the arrow, the more flex it will have compared to a shorter, stiffer arrow. Arrow length should be measured from the throat (deepest part) of the nock to the cut end of the arrow shaft. This can easily be done by drawing your bow and having someone mark about an inch in front of your rest. Arrow Length – The first step in choosing the correct arrow spine in determining your arrow length.This means that in a pack of arrows, the shafts will all be within +/-.003” straightness of each other. Straightness tolerances are usually between +/-.006 (less consistent) to +/-.001 (more consistent).įor example, your average arrow usually have a straightness tolerance of +/-.003”. In general, the higher the number the cheaper the arrow and the less consistency in straightness there will be. It also measures the consistency in how straight each arrow is. Straightness Tolerance – The straightness tolerance of an arrow is the measurement of the consistency in how straight each arrow is compared with one another.This number is important if you want to build a heavy or light arrow. For most hunting arrows, GPI ranges from 8-10. This means that for every inch of an arrows shaft, it will weigh a certain amount. GPI – GPI stands for “grains per inch” of arrow.In general, stiffer spines with a lower number tend to weigh more and have a heavier grains per inch of arrow length. Arrow shafts with a lower spine number, tend to be stiffer (ex: 300). Arrow shafts with a higher spine number, tend to be more flexible (ex: 500). Spine Number – The spine number of an arrow refers to its flexibility, or degree of stiffness.The key is finding the correct balance of peak draw weight and arrow spine for optimal performance. For low poundage bows, you want to use a more flexible arrow that will bend more. Alternatively, if an arrow has a spine that is too stiff, it will be less forgiving when released from the bow and will go in different directions.įor high poundage bows, you want to use a stiff arrow (lower number). If an arrow has too much flex, it will not recover correctly when released from the bow, resulting in inconsistent accuracy. This is because spine rating determines how an arrow responds to a bow. You can spend top dollar on a brand-new bow, but if you are shooting arrows with an incorrect spine, you will quickly become frustrated due to inaccuracy. Spine is important for accuracy and consistency. Arrow spine ratings for compound bow arrows usually range anywhere from 200 to 700. An arrow with a higher spine number will tend to be more flexible and bend easier, whereas an arrow with a lower spine number will tend to be stiffer. In other words, spine is the measurement of how much an arrow bends. In simple terms, the spine rating of an arrow is the measure of its stiffness. What is Arrow Spine and Why is it Important?Īs an arrow is released from a bow, the arrow shaft flexes due to the force applied by the bow string.
#ARROW SPINE CHART HOW TO#
This article will cover details and importance of arrow spine, what arrow spine numbers mean and how to choose the correct arrow spine for your bow.
#ARROW SPINE CHART FULL#
No matter how good of a shot you are, you will never realize your full potential with an incorrectly spined arrow. When choosing a hunting arrow, spine rating is the most important aspect of selecting the correct arrow. An arrow that is too flexible or too stiff will cause inconsistencies down range and lead to frustration. This is why it is important to shoot an arrow that is spined correctly for your specific bow. Choosing the correct arrow spine for a compound bow can make a big difference in your accuracy and arrow groups. These are all common words that hunters consider when deciding on a hunting arrow. Stiff, flexible, light, heavy, speed and penetration.