Looking to buy some bamboo shafts to finish into arrows. When I plugged the info for the 60# bow (cut to center) at 28" draw it puts the recommended dynamic spine range at about 64-70#. Plugging in the info for tapered bamboo arrows, with assumptions on GPI and end diameters based on seller claims, with a 125gr point and 2" dowel in the tip, it's telling me I should get 80-85# static spine shafts at 29.5". Of course you cut them long and tune to account for form variations, but does that seem right to you guys? Or does 80-85# seem high? Most recommendations I see for wood shooters is to add 5# to the bows weight to get close.
I want to only have to order once, because they ship from overseas, meaning it'll be weeks of waiting and higher volumes of shafts.
Sounds about right to me.
I shoot #60 @ "30 and use 75-80 bamboo. I shoot a"33 or close to it arrow with a 145gr. tip and my bow isn't cut to center. It seems to me that the bamboo take about #10 more spine for some reason.
Denny
For a cut to center bow 80/85's don't sound out of line at all. Of course you'll be fine tuning them to length.
I had a RC bow scaling in at only 54# that was cut 3/16" past...PAST center and had to go 80# to get them to fly!
Center cut on riser has a huge influence on spine, it seems...
Had a test kit once, that shot weak out of my 3/16" riser at 54# and also from another 3/16" at 50# of a friends. Along comes a guy with a 65# LB, that was cut IBO Legal at 1/8" SHY of center... and those same arrows shot STIFF out of his bow..same draw length, etc.
10-15# more draw weight and his 1/8" shy of center riser threw them stiff, ours much lower but cut well past center = weak.
Seems riser cut is a big issue...?
Many factors come into play. How the riser is cut, your release, the stiffness of the shaft in question (with decided upon weight up front), and how thick that shaft is to name a few. A 5/16" shaft may allow certain latitudes that you can't get with a 3/8" shaft.
ChuckC
Awesome, thanks for the replies!