how to determine spine?

[seif5034]

how is the spine rating determined with a traditional bow?
 For EX:
At the moment I own a fiberglass bow. it shoots 25# @ 28" and 58" long.

 I've just been shooting spare arrows that I have laying around. 2119 alums for the most part but I'm sure those are not ideal.

[Cherokee Scout]

A 2119 is far too stiff spine for a 25# bow.
To determine if a shaft is too stiff or too weak, shoot a shaft with no feathers.
Stand about 15 -20 feet from the target.
If you are right handed, the arrow will curve in flight to the left, it will hit the target with the nock right, point left. Opposite if it is too weak.

[seif5034]

I figured they were off one way or the other.

 I found the instructions on your website and It all makes a lot of sence. Thanks