Arrow rotational energy

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N2TRKYS

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Group size, getting them to hit the same area consistently. When I can hold say a 5" group at 50 yards with fieldpoints and I put broadheads on and it opens up to say 8-9" I have issue with it. Now I feel like my groups are pretty equal in size between fieldpoints and broadheads. Slightly better with fieldpoints, that's to be expected.


Yeah, that ain’t good. What was the thing that you think had the most impact on correcting that?
 

Billy Goat

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Yeah, that ain’t good. What was the thing that you think had the most impact on correcting that?


I think the biggest factor is straight arrows, after you have those you need to make sure the ends are cut true, I don't always see a big difference in squaring the ends of my shafts, however my saw is setup just right, a poorly setup arrow saw can really mess up the cuts. I used to spine align the arrows on a spine tester, found that to be a waste of time but nock tuning before fletching has shown to be worth the time, that might even be better than the straightness actually.

For starters you need arrows that spin evenly, broadheads that don't wobble, nocks that make even contact on the shaft. I have some arrows that just flat out won't shoot, can't figure it out, they seem fine in every way I can check them. I have seen a nock make an arrow fly 4" low at 20 yards, no outward evidence why, just could put that nock on a different arrow and it would do it to that arrow as well.

Those are factors that pop out at me immediately, I'm sure I'll think of more as time allows.
 
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N2TRKYS

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I think the biggest factor is straight arrows, after you have those you need to make sure the ends are cut true, I don't always see a big difference in squaring the ends of my shafts, however my saw is setup just right, a poorly setup arrow saw can really mess up the cuts. I used to spine align the arrows on a spine tester, found that to be a waste of time but nock tuning before fletching has shown to be worth the time, that might even be better than the straightness actually.

For starters you need arrows that spin evenly, broadheads that don't wobble, nocks that make even contact on the shaft. I have some arrows that just flat out won't shoot, can't figure it out, they seem fine in every way I can check them. I have seen a nock make an arrow fly 4" low at 20 yards, no outward evidence why, just could put that nock on a different arrow and it would do it to that arrow as well.

Those are factors that pop out at me immediately, I'm sure I'll think of more as time allows.

That’s odd for sure. Isn’t nock tuning in essence spine aligning?
 

Reburn

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That’s odd for sure. Isn’t nock tuning in essence spine aligning?

dynamic spLine yes. Different from static spine

From AT
The two are used to basically describe the same thing. But generally they are meaning this: Spine = how much an arrow bends as measured when a 1.94lb weight is hung from the middle of a 28" length piece of shaft. Spline = which "side" of the arrow bends the least/most. .
 

Billy Goat

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That’s odd for sure. Isn’t nock tuning in essence spine aligning?

Yes and no. The idea is you can find the weak spine area on a spine tester, once you locate this and position it in the same place on each arrow they should each react the same, in idea it's good, in practice it's not as accurate as actually nock tuning. Also carbon arrows are a lot more consistent than they used to be, can be hard to find a weak spine section on some anymore.

@Reburn gave the fancy definition. I gave the redneck hold by beer and try this direction.
 
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N2TRKYS

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Yes and no. The idea is you can find the weak spine area on a spine tester, once you locate this and position it in the same place on each arrow they should each react the same, in idea it's good, in practice it's not as accurate as actually nock tuning. Also carbon arrows are a lot more consistent than they used to be, can be hard to find a weak spine section on some anymore.

@Reburn gave the fancy definition. I gave the redneck hold by beer and try this direction.


Ok, I’ve never done or messed with either. I’ve just been told that it was basically the same by other folks that do it.

You’d probably have a stroke if you were shooting the GT Expedition Hunters like I always shot. Lol
 

Billy Goat

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Ok, I’ve never done or messed with either. I’ve just been told that it was basically the same by other folks that do it.

You’d probably have a stroke if you were shooting the GT Expedition Hunters like I always shot. Lol

I shoot what was sorted out of those.
 

Reburn

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Ok, I’ve never done or messed with either. I’ve just been told that it was basically the same by other folks that do it.

You’d probably have a stroke if you were shooting the GT Expedition Hunters like I always shot. Lol

bear with me because the definitions are important.
The techinal definition is
Spine = how much the arrows bends at 28" long with a 1.94 lb weight on it. IE 250 is stiffer aka less deflection the a 300 and so forth. Except carbon express. They label completely different.
Spline = the point on the arrow that is actually bending the 300. not all the arrow will bend equally as you rotate it so its easiest to find the part on the arrow that deflects the most.

LIke billy goat said nock tuning and ram testing for spline are in theory the same. Run your arrow out on a ram spine tester and mark the place on the arrow that bends the most and then locate it however you want on your bow. This is called locating your weak spline. In theory all your arrows should be tuned and flexing the same way when they come out of the bow. In practice it doesnt really work very well.

Nock tuning is spinning the nock 90 degrees each time shooting bareshafts through paper or grouping or any other way until they all react the same way and you dont have any fliers. Some guys even do this out of a hooter shooter. This method is very effective. Most of your good pro shooters absoultely nock tune.

IME nock tuning works much better then trying to locate weak spline on a ram tester. A ram tester is only good to test spine deflection and runout in my opinion.
 
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N2TRKYS

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bear with me because the definitions are important.
The techinal definition is
Spine = how much the arrows bends at 28" long with a 1.94 lb weight on it. IE 250 is stiffer aka less deflection the a 300 and so forth. Except carbon express. They label completely different.
Spline = the point on the arrow that is actually bending the 300. not all the arrow will bend equally as you rotate it so its easiest to find the part on the arrow that deflects the most.

LIke billy goat said nock tuning and ram testing for spline are in theory the same. Run your arrow out on a ram spine tester and mark the place on the arrow that bends the most and then locate it however you want on your bow. This is called locating your weak spline. In theory all your arrows should be tuned and flexing the same way when they come out of the bow. In practice it doesnt really work very well.

Nock tuning is spinning the nock 90 degrees each time shooting bareshafts through paper or grouping or any other way until they all react the same way and you dont have any fliers. Some guys even do this out of a hooter shooter. This method is very effective. Most of your good pro shooters absoultely nock tune.

IME nock tuning works much better then trying to locate weak spline on a ram tester. A ram tester is only good to test spine deflection and runout in my opinion.

Good deal. Maybe that’ll help somebody that’s gonna be doing that.
 
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N2TRKYS

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I shoot what was sorted out of those.

Mine were all ordered online, prefletched and cut with inserts already glued in when delivered.

I recently increased my poundage, so I had to up spine. I tried some GT Hunter XT and Black Eagle Carnivores arrows. I’ve been getting the same type of accuracy with these as the Expedition Hunters.
 

Billy Goat

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Mine were all ordered online, prefletched and cut with inserts already glued in when delivered.

I recently increased my poundage, so I had to up spine. I tried some GT Hunter XT and Black Eagle Carnivores arrows. I’ve been getting the same type of accuracy with these as the Expedition Hunters.


As long as your happy that's what matters. Right now in my elk setup I'm using .001 carnivores. My whitetail setup is the GT Pro Hunters (.001). I use the xt and .003 carnivores for practice and shoot around arrows. Went through 3 dozen XT hunters to find a half dozen that spined out close to what my pros were. Tune with the .001's. I'm a little anal with stuff.
 
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N2TRKYS

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As long as your happy that's what matters. Right now in my elk setup I'm using .001 carnivores. My whitetail setup is the GT Pro Hunters (.001). I use the xt and .003 carnivores for practice and shoot around arrows. Went through 3 dozen XT hunters to find a half dozen that spined out close to what my pros were. Tune with the .001's. I'm a little anal with stuff.

I’m still playing around with different weights right now. Gotta make a decision soon and set my sight tape.
 

Brendan

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bear with me because the definitions are important.
The techinal definition is
Spine = how much the arrows bends at 28" long with a 1.94 lb weight on it. IE 250 is stiffer aka less deflection the a 300 and so forth. Except carbon express. They label completely different.
Spline = the point on the arrow that is actually bending the 300. not all the arrow will bend equally as you rotate it so its easiest to find the part on the arrow that deflects the most.

This is not correct. There is no "Spline" in archery, only "Spine" - coming from stiffness, or backbone. Don't listen to that garbage on ArcheryTalk.

Your "Spine" = "Rated Spine" or "Static Spine"

The definition of spline: "A rectangular key fitting into grooves in the hub and shaft of a wheel, especially one formed integrally with the shaft which allows movement of the wheel on the shaft." or, "a slat" or as a verb: "secure (a part) by means of a spline." Most of the time, it's just someone mis-spelling "Spine" and some people over on ArcheryTalk started trying to use it as an actual word, but it was done so 100% incorrectly.

What you're starting to get at is spine variation in the shaft (and between arrows in a batch), and the stiff / weak and neutral planes of the shaft, as well as what's called residual bend. if you put your arrow on a Ram, support it with the rated weight, you'll see that actual measured spine will vary +/- dependent on the quality of the arrow and as you rotate it through 360 degrees.

You can go down the rabbit hole with this if you want to - frequency analyzers and such, but it's easier to just shoot an arrow with the appropriate "spine" and nock tune if needed.
 

Billy Goat

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This is not correct. There is no "Spline" in archery, only "Spine" - coming from stiffness, or backbone. Don't listen to that garbage on ArcheryTalk.

Your "Spine" = "Rated Spine" or "Static Spine"

The definition of spline: "A rectangular key fitting into grooves in the hub and shaft of a wheel, especially one formed integrally with the shaft which allows movement of the wheel on the shaft." or, "a slat" or as a verb: "secure (a part) by means of a spline." Most of the time, it's just someone mis-spelling "Spine" and some people over on ArcheryTalk started trying to use it as an actual word, but it was done so 100% incorrectly.

What you're starting to get at is spine variation in the shaft (and between arrows in a batch), and the stiff / weak and neutral planes of the shaft, as well as what's called residual bend. if you put your arrow on a Ram, support it with the rated weight, you'll see that actual measured spine will vary +/- dependent on the quality of the arrow and as you rotate it through 360 degrees.

You can go down the rabbit hole with this if you want to - frequency analyzers and such, but it's easier to just shoot an arrow with the appropriate "spine" and nock tune if needed.


I got no idea. I stay away from AT.

I'll say around here it's more common to be annunciated as spline. We talk funny tho
 

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I got no idea. I stay away from AT.

I'll say around here it's more common to be annunciated as spline. We talk funny tho

Ha. Agree it's more common in some places. But, if getting into definitions like this thread did - it is definitely not correct. It gets mis-used in the fishing rod world too...
 

Reburn

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Ha. Agree it's more common in some places. But, if getting into definitions like this thread did - it is definitely not correct. It gets mis-used in the fishing rod world too...

Shit works for me its easier not to have to enunciate the L anyways. Good to know I just got fed incorrect info not that i didnt understand it. Hard to say over there what is imaginary rabbit holes and what is real. I saw the oscilation frequency testing and decided I didnt need that rabbit hole. Especially when nock tuning seems to accomplish the same thing easier and more consitently.

I never could rotate my stock ram tester well enough to get good enough reading with the weight to determine weak side so I just use it for runout. I cheat some on runout too as 28" standard on runout doesnt do me much good on 29.5" arrows.
 

Billy Goat

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Shit works for me its easier not to have to enunciate the L anyways. Good to know I just got fed incorrect info not that i didnt understand it. Hard to say over there what is imaginary rabbit holes and what is real. I saw the oscilation frequency testing and decided I didnt need that rabbit hole. Especially when nock tuning seems to accomplish the same thing easier and more consitently.

I never could rotate my stock ram tester well enough to get good enough reading with the weight to determine weak side so I just use it for runout. I cheat some on runout too as 28" standard on runout doesnt do me much good on 29.5" arrows.

It use to be easy to find the weak spine area on carbon, arrows have improved a lot. Too hard to find it on many arrows now. Definitely notice a difference rotating nocks, sometimes it's very slight turning as well.


Something I never really tried was changing where the weight was, I wonder if sometimes the weak section spun around the shaft instead of a straight line down it. Maybe move the weight off center and see if the weak section still shows in the same spot. That would explain why the two processes give different results.
 
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N2TRKYS

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It use to be easy to find the weak spine area on carbon, arrows have improved a lot. Too hard to find it on many arrows now. Definitely notice a difference rotating nocks, sometimes it's very slight turning as well.


Something I never really tried was changing where the weight was, I wonder if sometimes the weak section spun around the shaft instead of a straight line down it. Maybe move the weight off center and see if the weak section still shows in the same spot. That would explain why the two processes give different results.


When you notice this difference in rotating nocks, is it with field points or broadheads only?
 
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