AMO and IBO speed tests and correct arrow spine?

[ACLakey]

Does anybody know this one?

When bow manufactures test they’re bows to the AMO and IBO standards do they use an arrow that is correctly spined, or do they use one that is just the correct weight?

If the arrow is under spined won’t you loose some of the bow’s energy due to the shaft wildly deflecting? If that is the case doesn’t it stand to reason the speeds would test out slower with an underspined arrow than with a correctly spined arrow of the same weight because some of the forward motion is translated into a deflection in the shaft.

I am going to ask a Physics and FEA prof this one Monday. Anybody want to take a stab at this one?


>>>----Andrew---->

[Rangeball]

I think your theory is correct, although I have no idea how large or miniscule the fps difference might be. Let us know what the Prof says.

[TheArcheryProgram]

The effects at the bow and what a chrono can see and report are negletible at best. I have done this test many times and can't definatively say it effects the speed reading.

Downrange is another story however! The effects of mismatched arrows are not only obvious, but easy to quantify by measuring group size etc.

That's my stab!



>>>------Tony Virnoche------>>>
>>>---The Archery Program--->>>

[ACLakey]

Thanks Tony. By the way great program

>>>----Andrew---->

[pdq 5oh]

ACL, I'd have to agree with Tony. Right out of the bow, where I'd say they measure, it probably makes little difference. Downrange with all the deflection of an under-spined arrow there is most likely a difference. My guess.

Phil.
"Could you guys be quiet, my dad's trying to shoot."