say i have a 28" arrow spined #40-45. if i cut it back to 26"bop, how much has the spine increased? thanks.
Static or Dynamic? - the arrow stays the same - who you foolin'
my understanding was that if an arrow is spined at a particular length, said spine increases as you decrease the length of the arrow. the spine gets stiffer. this is what i'm trying to find out.
My spine test is set for 26" O.C. and calibrated to give spine for a 28" arrow. If you take an inch off the arrow, you could expect to shoot it out of a bow about 5 lbs heavier at 27". A 26" should shoot out of one 10 lbs heavier at 26". I think you can get a spine chart online at 3Rivers. It is for Aluminum/carbon and wood with recurves or longbows. Don't forget to allow for weight up front.
http://www.3riversarchery.com/pdf/ArrowCharts.pdf
thank you for the link. i just printed a couple copies of the chart. also forgot to mention my question was with regard to wood arrows.
In a manner of speaking, rraming is correct. Shortening the shaft does not change how it will read on a spine tester, that's the static spine.
Shortening, or lengthening, the shaft will change the dynamic spine, the way it shoots out of a bow.
If I remember right, 1" of length equals about 5# of dynamic spine. That's for a shaft longer or shorter than 28".
Shorter shaft = higher dynamic spine.
Longer shaft = lower dynamic spine.
Clear as mud, right?
Guy
thanks, guy. that's what i was looking for; the #5 per inch. i thought that's what it was, but wasn't sure. memory------.