Why the chart gives you a starting point, not an answer
Recurve spine charts work by drawing weight, arrow length, and point weight — and they produce a spine range. That range is wide by design, because it has to cover every bow and every archer shooting at that draw weight. Your bow is not average. Your draw length, your limb efficiency, your release quality — none of these are the chart's median. The chart gets you close. It does not get you to the right arrow.
The spine hunt that follows — trying stiffer, trying weaker, paper tuning, bare shaft testing — is the process of finding what the chart could not tell you. ALR skips most of that. It gives you the exact spine for your setup from your numbers, not from an averaged lookup table.
What ALR is
ALR — Axial Load Ratio — is the ratio of the compressive force your bow applies to the arrow divided by the force required to buckle that shaft. A shaft that is correctly matched to your setup will flex the right amount through the shot and recover cleanly. One that is too weak flexes too much; one that is too stiff barely flexes at all. ALR gives you a single number that captures both sides of that equation: how hard your bow hits the arrow, and how much resistance the shaft provides. The spine chart gets you in the neighborhood. ALR tells you whether you are actually matched.
The recurve target ALR
Analysis of recurve chart recommendations across draw weights and arrow lengths — treating the chart as empirical ground truth and back-calculating ALR — produces a tight cluster around a single value.
Correctly matched recurve setups across draw weights from 30 lb to 60 lb, arrow lengths from 26″ to 30″, and standard carbon shaft recommendations cluster between 1.83 and 1.94 with a mean of 1.9. Unlike compound, there is no use-case band. There is one target. The Paradox requires a specific flex range to function, and the chart has always been aiming at it.
This is the structural difference between recurve and compound spine selection. Compound has a range — competition, hunting, recreational — because a mechanical release can tolerate varying flex levels and the arrow never has to navigate around a riser. Recurve does not have that tolerance. The Paradox geometry demands a specific flex. ALR 1.9 is where that geometry works.
Use your actual draw weight
Enter the draw weight you are shooting — the weight you have dialed in, at your draw length.
Recurve ALR calculator
Find your spine — enter setup, get spine
| Spine | ALR | vs target |
|---|
Using these results
ALR 1.9 is the starting spine, not the final arrow. Once you have the correct spine class, bare-shaft tuning at distance confirms the dynamic spine is landing where it should. A bare shaft hitting left of fletched (for a right-handed archer) means the arrow is exiting stiff — move to the next weaker spine or add point weight. A bare shaft hitting right means it is exiting weak — move stiffer or reduce point weight. ALR gets you into the right spine class. Bare-shaft tuning locks in the exact setup within that class.
When approaching your target ALR, we recommend stepping into the ideal position from the weak side — start with a slightly longer arrow than your final cut length. This keeps your dynamic spine on the weak end of the window during initial tuning, giving you room to shorten into the correct position rather than backing out of an arrow that is already too stiff.
Keep in mind that not every combination of draw weight, arrow length, and point weight will produce a workable result. The tuning window is narrow — small changes in any variable can push the setup outside it. If a given combination does not respond to bare-shaft tuning as expected, adjust one variable at a time and recheck ALR before continuing.
The chart used to give you the spine class. Now ALR does — more precisely, and without the adjustment tables.
Published 2026-08-18 · Axial Bowstrings