Spine Chart Confusion

[AlabamaMountainMan]

I am mapping out a new arrow build for a Warf I am piecing together and the spine charts don't "feel" right to me. I am looking into the Easton Carbon Legacy 5mm Fred Eichler shafts. The bow will be 40lb @ 28" but probably closer to 41-42lb at my draw length.

I plan on using the Simmons 200g interceptor along with the standard insert that comes with the shaft (16g).
- 200g Broadhead/FP
- 16g insert
- 34" shaft
- 4 4" parabolic feathers (2.75g/feather I think)
- 15g illuminated nock
Total weight will be around 540g depending on the exact spine I select.

The confusion comes from Eastons spine chart which says to add 3lb for every 25g over 100g on the point. Since I am using a 200g point, that would mean I need to get spine for a 54lb bow. According to Easton, that means I need a 300-250 spine. Does that seem right? I don't ever see anyone posting on forums or on youtube using 250 spine arrows. Most guys are shooting 40lb-45lb recurves, shooting 600-700g arrows with most of the weight in the insert or broadhead, and still using 400 spine arrows. Additionally, Easton doesn't even make this arrow in anything lower than 340 spine. No 300 or 250. What am I missing/not understanding?

 

[archp625]

The best luck I have had with spine charts and being pretty close is the Black eagle Spine chart.

Black Eagle Arrows Spine chart | by Black Eagle Arrows

Find the perfect arrows for your bow with the Black Eagle Arrows Spine chart. Compare different arrow sizes and spines to improve your archery game.

blackeaglearrows.com

I don't shoot their arrows, but it's been pretty accurate. As always, you still need to tune your arrows to your bow.

 

[AlabamaMountainMan]

The best luck I have had with spine charts and being pretty close is the Black eagle Spine chart.

Black Eagle Arrows Spine chart | by Black Eagle Arrows

Find the perfect arrows for your bow with the Black Eagle Arrows Spine chart. Compare different arrow sizes and spines to improve your archery game.

blackeaglearrows.com

I don't shoot their arrows, but it's been pretty accurate. As always, you still need to tune your arrows to your bow.

Hmm, that also seems to imply a 300 spine. So you don't think that seems too stiff being in the 300-250 range? I am just confused why so many folks can use 400 spines with super heavy, high FOC arrows when the charts don't seem to recommend that. Unless folks are cutting the arrows shorter.

 

[archp625]

I do not. You are shooting a 34" arrow. If you were shooting a shorter arrow then yes. Does it have to be a 34' arrow or do you think you will cut it down a little to tune it to your bow? I am only asking because I would go with a 350 arrow if you plan on cutting it a little.

 

[Beendare]

IME, The limbs will make a big difference...for example cheap limbs vs high energy Uukha limbs, the Uukhas need more arrow spine.

use the free Stu Miller calculator to get you close...but only if you input data correctly

 

[AlabamaMountainMan]

I do not. You are shooting a 34" arrow. If you were shooting a shorter arrow then yes. Does it have to be a 34' arrow or do you think you will cut it down a little to tune it to your bow? I am only asking because I would go with a 350 arrow if you plan on cutting it a little.

I considered trying the 34" to shrink the gap a bit, but I am not opposed to cutting to 31" since I use a 31" now and don't dislike my gap. I don't think I would want to cut below 30".

 

[AlabamaMountainMan]

IME, The limbs will make a big difference...for example cheap limbs vs high energy Uukha limbs, the Uukhas need more arrow spine.

use the free Stu Miller calculator to get you close...but only if you input data correctly

Unfortunately idk that I would be able to provide all the data needed. I definitely would not be using Uukha limbs, but I won't be buying the amazon special either. I was considering the DAS clear burl limbs.

 

[archp625]

I considered trying the 34" to shrink the gap a bit, but I am not opposed to cutting to 31" since I use a 31" now and don't dislike my gap. I don't think I would want to cut below 30".

This may be against some popular opinions, but have to tried doing a fixed craw? Tune the arrow to your bow. So 1-2" past the riser for safety and then put a brass nock below your double nock and play with it to get exactly what you want for your point on?

 

[AlabamaMountainMan]

This may be against some popular opinions, but have to tried doing a fixed craw? Tune the arrow to your bow. So 1-2" past the riser for safety and then put a brass nock below your double nock and play with it to get exactly what you want for your point on?

Yepp, I am doing that now. It's my preferred way to shoot. It has my point on at about 25 yards and manageable gap for everything below that. I just figured longer arrow would shrink the gap even more. Not a necessity if it causes problems for me in the long run.

 

[BigHink66]

IMO, at 31 inches from a 41 pound bow with 200 grains up front... 400 is the stiffest I would go. And I think you could get away with a 500.

Just based on my past experience.

I currently shoot a 350 at 31" with 225 grains up front and 60lb draw.

 

[AlabamaMountainMan]

IMO, at 31 inches from a 41 pound bow with 200 grains up front... 400 is the stiffest I would go. And I think you could get away with a 500.

Just based on my past experience.

I currently shoot a 350 at 31" with 225 grains up front and 60lb draw.

Gotcha. I have some 350 and 400 spines all at 31". I guess I'll try them out to get an idea of stiffness before I buy any new arrows. I just cannot imagine I need a 250.

 

[BigHink66]

I would not be suprised if 400 is stiff and will need more weight up front. Being a warf and centershot should help.

 

[AlabamaMountainMan]

I would not be suprised if 400 is stiff and will need more weight up front. Being a warf and centershot should help.

That would be nice. I may wind up with the 225 Safari instead of the 200g interceptor to get the slightly wider cut so there may be a little bit extra weight added.

 

[Beendare]

My bows past center shot will shoot stiffer shafts, they seem to like them better.

You can shim your side plate and play with that- in and out- to get the arrows that you do have to tune.

 

[AlabamaMountainMan]

My bows past center shot will shoot stiffer shafts, they seem to like them better.

You can shim your side plate and play with that- in and out- to get the arrows that you do have to tune.

I was planning on buying the Hoyt Satori side plate to tinker with that. The riser doesn't have a plunger hole so I can't use something like an accutune.

At this point it sounds like I'll just being tinkering with different spines and lengths for a while. Guess that's half the fun.

 

[Beendare]

Guess that's half the fun.

Or Not!

You can get different thicknesses of the furniture pads with a sticky side that work well.

 

[Beendare]

This is always a problem for guys getting started.

Dialing in your arrow spine is a waste of time until you have a consistent DL....variations in Draw length and form flaws affect an arrows spine big time.

Once you have that form fairly consistent, measure everything for the Stu Miller or 3 Rivers calculators and that get's you close before purchasing a bunch of different spine arrow shafts.

From that point I set up one bare shaft arrow a little long, hot melt a temporary insert and start shooting. I have the 3 rivers FP test kit- a variety of FP's from 70g to 300g that I use to determine what the bow likes before I start cutting shafts.

I don't know if there is an exact correlation of tip weight to how much you cut or go up in spine- every setup is different. The stu miller for me has been within 50g of tip weight to get the bare shafts flying like darts at 20y.

If you are a guy that thinks you need very high FOC -[Hint- you don't, it doesn't do anything]- this process makes it especially easy.

 

[AlabamaMountainMan]

This is always a problem for guys getting started.

Dialing in your arrow spine is a waste of time until you have a consistent DL....variations in Draw length and form flaws affect an arrows spine big time.

Once you have that form fairly consistent, measure everything for the Stu Miller or 3 Rivers calculators and that get's you close before purchasing a bunch of different spine arrow shafts.

I was a little confused on the 3R calculator where it gives the dynamic spines and says they should almost be the same but the bow number is "50" and the arrow number would be "497" or something similar. I am about to add a clicker to my current bow and put one on the Warf to help get my draw a little more consistent. It's not currently bad, but could definitely be better.

From that point I set up one bare shaft arrow a little long, hot melt a temporary insert and start shooting. I have the 3 rivers FP test kit- a variety of FP's from 70g to 300g that I use to determine what the bow likes before I start cutting shafts.

I had a weird scenario the other day where my field points were flying great, but when I put on a broadhead (Zwickey Delta 2 blade) they hit high left and were very unstable, but only on 3 feather arrows. 4 feathers fly great. BH and FP were the same weight, but I guess the broadhead was steering the arrow too much.

I don't know if there is an exact correlation of tip weight to how much you cut or go up in spine- every setup is different. The stu miller for me has been within 50g of tip weight to get the bare shafts flying like darts at 20y.

If you are a guy that thinks you need very high FOC -[Hint- you don't, it doesn't do anything]- this process makes it especially easy.