Arrow spine

[archp625]

When I look up how to measure the spine of an arrow, its 26" with a 2-pound weight in the middle. When I look at Easton Legacy arrows, it says measured at 28." So would an Easton Legacy 340 act more like a 400. When I am bare shaft tuning my bow it sure seems like it. But when I shoot a GT Traditional 340 its way too stiff for about the same spec arrow. I know I should go off what I see and shoot but everything is telling me a 340 Legacy is too stiff, it just does act like it.

 

[Mighty Mouse]

The old ATA spine test procedure used a 2 lb weight suspended from the midpoint of a 26” section of shaft. The modern ASTM procedure uses a 1.94 lb weight and 28” section of shaft. This document shows how to convert between the two methods: http://oakcreekarchery.com/wp-content/uploads/2010/06/Spine-Instructions2.pdf

 

[archp625]

The old ATA spine test procedure used a 2 lb weight suspended from the midpoint of a 26” section of shaft. The modern ASTM procedure uses a 1.94 lb weight and 28” section of shaft. This document shows how to convert between the two methods: http://oakcreekarchery.com/wp-content/uploads/2010/06/Spine-Instructions2.pdf

Ahh ok. So more than likely the GT's are tested the same way as the Eastons.