arrow spine

[burkenashu]

i was watching ryan gills spine video he says that spine doesnt matter in primitive archery thoughts

[sleek]

Id be interested in watching that video, would you post a link?

[WhistlingBadger]

Ryan used to show up on the forums once in a while.  I miss seeing him around here--he seems like a good guy.

If I remember right, Ryan shoots over-spined arrows with very light, stone points.  He talks about it at some length in one of his books.  I don't remember the whole point, but there is more to it than "spine doesn't matter." 

[burkenashu]

https://www.youtube.com/watch?v=TzRMKhxBU9w

[Pat B]

If I remember, Ryan used cane and possibly natural hardwood shoots for arrows. With the natural taper of the cane and shoot shafts the spine has a range of poundages it can work well with. Longer arrows also helps.

[burkenashu]

ok i was just curious what yall thought

[bjrogg]

Spine might not matter in the physical sense. You can as Pat says use longer or shorter shafts. Lighter or heavier points.

What really matters is clean arrow flight. And the only way I know how to get that is by coming up with the right combination of stiffness, length and point weight to match the preferred dynamic spine of the arrow, for the bow and archer.

Bjrogg

[Pappy]

Don't know what I am doing wrong but it matters with my arrow. of course you can make them longer or shorter or add and take away weight but that all changes the spine. 
 Pappy

[Wyrda]

This is pretty much nonsense. Spine is just as, if not more important for bows without a cutout. You may be able to get away with overspined arrows to some degree, but I know underspined arrows shoot like crazy from my English longbow.

[archeryrob]

Like said above me, Physics doesn't change because its primitive. I've argued with these guys for 20 years that get into archery and suddenly know it all. They use long arrows that shoot dynamicaly the same as shorter arrows spined.

The latter half of this I wrote explains a lot of it.
https://boweyrsden.wordpress.com/2016/01/01/the-proper-spine-for-primitive-arrows/

https://boweyrsden.wordpress.com/2014/02/18/5-shaft-reduction-and-spine-qualities/

[WhistlingBadger]

I think you're all correct; spine does matter.  But I would add that Ryan Gill isn't some newby know-it-all.  He has probably forgotten more about primitive archery than I will ever know, killed dozens of animals with primitive gear, from small game up to bison, is consulted by university anthropology departments.  When he makes a claim I sit up and take notice, even if I don't understand it or it goes against what I know. 

I certainly wouldn't dismiss anything he says as nonsense without at least watching the video.  There's a lot more to it than "arrow spine doesn't matter."

[Chumash]

The important word is "SOMETIMES" and Ryan explains in the video what this "SOMETIMES" is, for him and his experiences.

[Tuomo]

Spine does matter!
If you’ve ever shot a bare-shaft test, you know it absolutely matters. And using a bare-shaft test is the only reliable way to determine the correct arrow parameters—it immediately shows whether an arrow is dynamically correct, too weak, or too stiff.

The old rule of 5# per inch of arrow length applies only when the bow’s draw weight is around 65–75#. The rule was “created” by Saxton Pope, who shot bows in that range. For weaker bows, the rule simply doesn’t hold. In reality, the correlation is non-linear. For example, with 35–40# bows, the “rule” is roughly 2.5# per inch. And so on.

It’s also commonly assumed that a 28" arrow requires spine matching the bow weight—for example, a 30# bow needs a 30# arrow. But again, in practice this varies from archer to archer. One shooter may need 35# or even 40# arrows, while another may need 25# arrows for the same 30# bow. A bare shaft test will tell the truth.

The cut-in window has no effect. The required arrow spine is the same for wide-handle bows, narrow-handle bows, or windowed bows. If you don’t believe it, do a bare-shaft test using the same bow with different handle widths.

And finally, arrow point weight has almost no effect on required shaft spine. A 25-grain change influences spine by about 1# or less. Again—shoot a bare-shaft test to see for yourself!

[bassman211]

Cut in window has no effect. Must be me, and thousands of other guys that know the closer to center shot the easier it is to tune a bare shaft of one , and some times 2 spines. Congrads on winning the bow of the month. Nice work.

[Tuomo]

A cut-in window has no effect on the optimal spine of the arrow. You can verify this with a bare-shaft test if you don’t believe it. However, the cut-in window does make arrows less sensitive to spine variation. With a cut-in window, tuning and shooting become easier because the arrows are less affected by spine variation, release inconsistencies, or other tuning issues. The wider the handle, the more sensitive everything becomes.

My point is that if the optimal static spine is, for example, 42#, it remains the same regardless of the handle width. But with a wide-handle bow, a 44# bare-shaft arrow may fly to the left (for a right-handed shooter), while with a cut-in window the same arrow may still fly straight.

Regarding the “correct” spine, it’s more of a statistical issue. I can shoot accurately with normal, fletched arrows even when the spine variation within the set is 10–15#. But arrows that don’t have the optimal spine will occasionally fly farther left or right. Over the long term, statistically, the arrows with the correct spine will land in the center most consistently. Again, it comes down to sensitivity to various factors (spine, bow, archer, etc.).