Doug McCoy Traditional Archery.
Copyright 2009 Doug McCoy
Webmaster: Contact Us
Webmaster: Contact Us
Before attempting to tell you exactly what spine you need we first need to ascertain your shooting style and setup. We must determine your
draw length first then your draw weight at that length. Remember that the specs on your bow are not necessarily the length that you draw
your bow. Get someone to help you measure your draw length - make sure to measure at least three (3) times so that you are getting a
consistent reading.
Now that you have your specifications for your equipment and yourself we can proceed.
The proper selection of spine seems to be one of the most difficult decisions to make, however it is really quite simple.
As a general guideline, start with your bow's weight when drawn to 28 inches. This means that when the bow is drawn such that it measures 28 inches from the string to the point where the arrow is nocked to the back of the riser (the part of the handle that faces away from you)5 pounds of spine weight should be added for each inch of your draw over 28 inches. If your draw length is less than 28 inches, subtract 5 pounds for each inch under. Add 5 pounds of spine for broadheads over 125 grains. If you have an extra fast bow, such as one with a fast flight string, an additional 5 pounds of arrow spine should be added.
As an example, your longbow or recurve pulls 60 pounds at 28 inches. Your actual draw length is 28 inches, then a spine weight of 60 pounds is warranted. If you draw this bow 27 inches, then we recommend a spine weight of 55 pounds. If you draw this bow 29 inches, then your spine weight is 65 pounds. Now, if you use a head which is greater than 125 grains, then add an additional 5 pounds to these spines. If you use a fast flight string on these bows, then add an additional five pounds.
Most bows of today will allow you a fair range of spines that will shoot properly off them.
A good number of Longbows, Selfbows and some Recurves are not what we would call center shot. This means that the rest (where the arrow lays on the handle) is actually beyond center of the string. Bows can be verified by eye for this - if the arrow tends to lean away from the riser (handle) then it is not a center shot bow. With this type of bow, you would subtract 5 pounds of spine weight. As an example, your selfbow pulls 60 pounds at 28 inches. If you actually draw this bow 28 inches, then an arrow spine weight of 55 pounds would be used.
Now that you have your specifications for your equipment and yourself we can proceed.
The proper selection of spine seems to be one of the most difficult decisions to make, however it is really quite simple.
As a general guideline, start with your bow's weight when drawn to 28 inches. This means that when the bow is drawn such that it measures 28 inches from the string to the point where the arrow is nocked to the back of the riser (the part of the handle that faces away from you)5 pounds of spine weight should be added for each inch of your draw over 28 inches. If your draw length is less than 28 inches, subtract 5 pounds for each inch under. Add 5 pounds of spine for broadheads over 125 grains. If you have an extra fast bow, such as one with a fast flight string, an additional 5 pounds of arrow spine should be added.
As an example, your longbow or recurve pulls 60 pounds at 28 inches. Your actual draw length is 28 inches, then a spine weight of 60 pounds is warranted. If you draw this bow 27 inches, then we recommend a spine weight of 55 pounds. If you draw this bow 29 inches, then your spine weight is 65 pounds. Now, if you use a head which is greater than 125 grains, then add an additional 5 pounds to these spines. If you use a fast flight string on these bows, then add an additional five pounds.
Most bows of today will allow you a fair range of spines that will shoot properly off them.
A good number of Longbows, Selfbows and some Recurves are not what we would call center shot. This means that the rest (where the arrow lays on the handle) is actually beyond center of the string. Bows can be verified by eye for this - if the arrow tends to lean away from the riser (handle) then it is not a center shot bow. With this type of bow, you would subtract 5 pounds of spine weight. As an example, your selfbow pulls 60 pounds at 28 inches. If you actually draw this bow 28 inches, then an arrow spine weight of 55 pounds would be used.
Spine Selection