Spine question

[Wolftrail]

So you have an arrow thats spined at 42# if leaving it longer by how much would  the dynamic spine decrease.  ie.  one inch longer decreases spine by how much..?

I think i worded that correctly.

[Roy from Pa]

Plus or minus 5# for every inch below or above 28 inches.

[Jack Denbow]

What Roy said.

[Wolftrail]

Why is it  "below or above 28 inches"  is that an AMO thing.  What if one draws  25".

[Roy from Pa]

28 inches is what all arrows are "static" spined at to group into spine weight.

Every inch longer than 28 inches, the arrow decreases in "dynamic" spine 5#

Every inch shorter than 28 inches the arrow increases in "dynamic" spine 5#

[Pat B]

...and that spine for a 28" finished arrow with a 125gr point. Point weight also affects spine. For each 25 grains or point weight over 125 you can decrease the dynamic spine by 5# and the opposite for under 125gr.

[Wolftrail]

Thanks, guys. "28 inches is what all arrows are "static" spined at "  probably read that a few years ago,  old age and senility seems to wipe out the memory.......  
 

Tip weight, I remember that one.   I use 125 gr. tips.