# How accurate are spine charts for traditional bows?



## TurbineBlade81 (Feb 26, 2018)

I'm sure this has come up before, but the chart on the GT website for example advises that for a 30# recurve with a 125 gr. point, you would shoot for the 500 spine arrows if they're cut to 29". Every post I've searched on this forum for "find me arrows for a 30# recurve" has resulted in advice closer to 600, 700, or even 800 spine arrows at that same length, draw weight, and point weight. 

I totally get that a lot of factors influence what an archer needs, but wouldn't 500 spine GTs be pretty stiff on a 30# recurve no matter what you do?

I'm just trying to reconcile the difference between the charts and word-of-mouth. I suspect the latter is closer to reality for most, but at least want to be close enough to be able to tune something, versus having to add so much point weight that arrows become impractically heavy. 

Thanks for your advice --


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## LDevine (Mar 13, 2014)

Do the 600 Velocity, with 50 grain aluminum insert, the inserts that come with it are 12.5 grain and too light for me to tune properly. I spend far too much money figuring that out.

I shoot a 32# OTF at 28in.

My arrows are 30in. Velocity 600’s, 100 grain screw in field point, 50 grain insert, Bohning 2.25 in X-Vanes.

Their cart about a spine size too stiff.


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## Doofy_13 (Jan 2, 2012)

Download stu millers spine chart xls


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## Nick728 (Oct 19, 2014)

A 600 Gold Tip traditional is about right and can be fine tuned by way of point weight and adjusting brace height. A 700 depending on you bow might be better, same adjustments apply. All charts err on the stiffer side and are only starting points. I just had this conversation with 3 Rivers and Lancaster. Easton website has a good spine selector as does 3 Rivers. One example: I have 3 bows @35#, each one uses a different spine arrow and point weight. In other words, it's trail and error to find a perfect match. Any difference in design, rest, plunger, side plate, center cut or brace height can change suggested selections. What is really important is the manufactures suggested arrow weight, a compound might call for at least 5 gpi per pound, most recurve suggest more. 
Nick


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## Easykeeper (Jan 2, 2003)

Try the spine calculator on the 3Rivers site...https://www.3riversarchery.com/dynamic-spine-arrow-calculator-from-3rivers-archery.html

With accurate inputs it should get you close and should be better than a chart. It will still be at best an estimate. There are so many variables involved that it's very difficult to be precise, ultimately you will need to tune if you want it right.


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## LDevine (Mar 13, 2014)

You wont find carbon much softer than 600 spine in a shootable length for adults. 700 or 800 might be fine with lighter point weight like 75 grains but then you may run into FOC issues. I think 600 should put you right on the money with some wiggle room to play with point weight.


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## Bow Rider (Jan 16, 2015)

The big difference in various peoples' experience and spine charts has to do with center cut and arrow rest on the riser of YOUR bow. If you play with the dynamic spine calculators, you'll see changing the center cut of the bow changes the appropriate arrow spine quite a bit. 
If your bow is cut past center and you are shooting off the shelf, the spine chart is probably about right. But if your riser and rest set-up requires the arrow to flex around the riser a bit, a weaker spine might be needed.


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## Don_Parsons (Feb 9, 2018)

Tag


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## LDevine (Mar 13, 2014)

Bow Rider said:


> The big difference in various peoples' experience and spine charts has to do with center cut and arrow rest on the riser of YOUR bow. If you play with the dynamic spine calculators, you'll see changing the center cut of the bow changes the appropriate arrow spine quite a bit.
> If your bow is cut past center and you are shooting off the shelf, the spine chart is probably about right. But if your riser and rest set-up requires the arrow to flex around the riser a bit, a weaker spine might be needed.


While center cut may make some difference, the charts still run stiff in my experience even with my cut past center riser, wire rest and plunger. 500 spine is what Gold Tip and Easton charts say. I still got nock right on a Block Foam target at various distances using the recommended spine. It wasn’t until I started shooting 600 that the arrows flew straight. 


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## Don_Parsons (Feb 9, 2018)

When buddy sold me my 35# recurve he made me up some 400 full length arrows, I found out later that they are way too stiff. 

I have a new bow that will range from 30# on up to 40# using the ILF family of limbs. I'll be testing 600 carbon spine shafts to see how they work. 

A Recurve archery fellow suggested that they should do the job, I picked up a test package of field points from 75gr on up to 200gr with everything in between. 

Easier to tune when I have it all handy. 

Learning curve 101 for sure. 

Don


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## TurbineBlade81 (Feb 26, 2018)

Thank you all for your help -- as much as I dont like some of what modern society has done to things I cherish, I can't say that having the internet as a free source of great information is one of them . I ordered some 600 spine arrows and some 100, 125, and 175 gr points to play around with for tuning...at least as something I'll get to eventually, once I shoot well enough. 

One thing that I find odd is the decrease in arrow length that seems to accompany the increase in spine. I guess this is because the makers assume that people who need 600+ spine arrows are just kids with short draw lengths, so producing 30" or larger arrows isn't economical to them (?). Anyway -- I guess we need to work with what we have! 

My wife is going to shoot a bow similar to mine, but with 25# limbs. Any advice on arrows for that poundage? Her draw is 27", but her set up with otherwise be identical to mine. 

Thanks again folks -- what a great forum.


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## Yard Dog (Oct 5, 2017)

That's what I did.... I draw 45#-54# depending on which bow I use... I had woodies for the heavier bow, but wanted to go to carbon, since I love them with my compound, and the 54#er wis a bit stout for me now....... I have Beman Hunter 400 and 500 arrows, ordered all the weights of tips, and have an arrow saw..... Gonna find out for myself......


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## DJ Hardy (Jan 18, 2016)

Turbin your wife will most likely need a 800 but a 700 may work with a lot of weight up front
I would try the 800 first full length and try different point weights
25 lb bows need light arrows to keep you happy. If you go too stiff the arrow will weigh more 
and you will need a heavier point to make it tune
The same thought process also applies to your 30# bow.
jmho


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## grantmac (May 31, 2007)

30#=700-800 with a 30" arrow unless you throw boat anchors on the front.
25#=900-1200 depending on arrow length.


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## TurbineBlade81 (Feb 26, 2018)

Ah -- you see, that's what I mean on the manufacturer's chart (at least GT's). I usually don't even see a recommendation on the charts for lower draw weight bows -- and I don't recall seeing 800+ spine arrows. I will try to reduce my strike plate thickness to bend those 600s a bit more, if it looks like I'm getting bad flight. (My bow is the sage riser, with the rug rest and plate). 

BTW -- can you increase center shot by removing the strike plate and replacing it with a tiny piece of "rug" placed at the very back of the shelf? It looks like you could move the arrow more center if the plate is all the way back (or more near the arrow point, if "back" isn't the correct archery term), if that makes any sense. There would be a big hole visible, but oh well. 

Something like easton 1616s for my wife's bow? I'll look around.

Thanks again folks -  Worst case scenario, I will shoot somewhat stiff arrows and just deal with them pulling to one side a bit. I'm still working on my release as is, so a bad release on my part probably does more than a stiff arrow....unfortunately.  I just didn't want to be so far off that I have no chance of developing form.


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## Nick728 (Oct 19, 2014)

Easton Carbon One arrows come in 1/2 spine sizes well under and over 800. Point sizes are variable some with break off availability. They can give a wide range of weight & point weight options, these are a thin shaft and not as high in price as other thin target shafts.
Nick


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## Bill 2311 (Jun 24, 2005)

If you can find the newest Stu Miller calculator, it will be close. That one allows for bow efficiency and centershot adjustments. 
Bow efficency really has an effect. I have a 19" ILF with 52# conventional recurve limbs that tunes for 29" .500 GT and 125 tips. My 52# Covert Hunter require .340 with same arrow length and tips.
See if you can borrow a couple or buy some singles from LAS to try.


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## maddog20/20 (Oct 13, 2015)

I ignore those and buy several spines and shoot them. I then grab the least weak one and cut it a half inch at a time to “true”

Many times, there are personal shooting eccentricities that affect the dynamic spine.


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## kynadog (Nov 3, 2004)

Bow Rider said:


> The big difference in various peoples' experience and spine charts has to do with center cut and arrow rest on the riser of YOUR bow. If you play with the dynamic spine calculators, you'll see changing the center cut of the bow changes the appropriate arrow spine quite a bit.
> If your bow is cut past center and you are shooting off the shelf, the spine chart is probably about right. But if your riser and rest set-up requires the arrow to flex around the riser a bit, a weaker spine might be needed.


Bow Rider is dead on. I have spent a lot of time researching this on line and talking to old time archers. You can see the effects of center cut most directly if you go to 3 Rivers Archery Dynamic Spine Calculator and putting in all your specs and then toggling through the different variables. A 0.125 difference in center cut makes more of a difference than 1" of arrow length or 25 to 50 grains of point weight. 

Check it out here: https://www.3riversarchery.com/dynamic-spine-arrow-calculator-from-3rivers-archery.html

As for the arrow charts, I have found them to be vastly inaccurate. Not really even a good starting point. In my experience, the Gold Tip chart would have over-spined my long bow by one, and in some cases, two spine classes.


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## cbc0905 (Apr 21, 2018)

I used the three Rivers calculator and it was pretty much dead on. 

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## Joe Hohmann (Oct 24, 2013)

If something does not feel right, try a different arrow. One of my bows is a 20# Martin that I bought for "new" people to try. A perfect match for it was supposed to be Easton Jazz 1716. Every shot landed far left. Tried them on my 30# Shakespeare...far left. Tried them on my 30# Hoyt PM5...far left. Tried my regular arrows, which are ICS Hunter Juniors, on the Martin...right-on. At first I just assumed the Martin was at "fault".


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## Bender (Dec 6, 2006)

This is really the conclusion that I have reached concerning the printed charts. They are wildly inaccurate for single string shooters. Except for when they are very accurate! 

It seems to be a "problem" that is caused by the fact that with a single string bow, there are more equipment variables, and WAY more individual form and execution variables that can have a greater impact on dynamic spine spine and arrow behavior than if you were shooting a fully rigged compound bow.


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## HonkAddict (Oct 18, 2011)

I've found that they can get you close... But the best bet is to buy a test kit of shafts. Especially because the charts don't factor in what kind of trad bow you're shooting or your point weight.
Some charts will have the cute point weights compound guys use, but nothing 200-400+ grains on the front end.

Best to get a close idea then buy a couple different spine shafts and put your desired weight on a full length shaft and trim it until it flies straight. 

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## Nick728 (Oct 19, 2014)

As mentioned, slight changes can make a huge difference. Yesterday an arrow that was weaker than the charts showed stiff. Slight adjustments showed, with bare shaft, the same arrow weak making the charts correct. Charts are a starting point that favor a stiffer side. Rest, brace height, plunger, no plunger, side plates, center shot, off the shelf, glue on rest, adjustable rest, arrow length, arrow point weight and lets not forget your release form are all variables that prove charts can only be a "safe" staring point. Requiring a half spine, full spine or several spines different than chart recommendations isn't unusual after tuning your bow to your form. Tuning a traditional bow is a labor of love, tuning a target bow can't be done without a great deal of testing by a very consistent shooter.
Nick


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## 3D Archery (May 19, 2016)

Byron Ferguson said this is what he does:

If using a Dacron string, subtract five pounds from your draw weight
If using a bow NOT cut to center, subtract five pounds from the draw weight - he also said it goes by how much it is not cut to center

So for me, using his formula, I need to look for arrows for a bow 10 pounds lighter


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## GCook (Aug 22, 2016)

cbc0905 said:


> I used the three Rivers calculator and it was pretty much dead on.
> 
> Sent from my ONEPLUS A5000 using Tapatalk


Yep

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