📏 Arrow Spine Selector Reference Chart
A general starting-point reference for arrow spine by draw weight. Always cross-check against your specific arrow manufacturer's spine chart, which also factors in arrow length and point weight.
What the chart is, and what it leaves out
The table is a fixed six-row lookup, SPINE_TABLE, keyed on one variable only: bow draw weight, from 20-29 lb at roughly 1000-800 spine down to 70 lb and over at roughly 340-250. Nothing is calculated and nothing to fill in.
The spine number is a deflection measurement. Under the ATA test a 1.94 lb weight hangs at the centre of a 28 in span and the sag in thousandths of an inch is the spine, so a 400 shaft bends 0.400 in and a lower number is stiffer.
Why draw weight alone cannot pick a shaft
Dynamic spine, how the arrow behaves at the shot, moves with more than draw weight:
| Change | Effect on dynamic spine |
|---|---|
| Longer shaft | Weaker |
| Heavier point or insert | Weaker |
| Shorter shaft | Stiffer |
| More draw weight | Needs a stiffer shaft |
Bow type matters too: a finger-released recurve bends the arrow around the riser and is fussier than a centre-shot compound shot with a release.
Frequently asked questions
What spine arrow do I need for a 60 lb bow?
This chart puts 60-69 lb at roughly 400-340 as a starting band, which is not an answer on its own: length and point weight can move it a full step either way. Look your combination up on the shaft maker's chart.
What does 400 spine mean?
Deflection in thousandths of an inch under the standard test: that shaft sags 0.400 in. So 340 is stiffer than 400, and 700 is much weaker.
What happens if an arrow is underspined?
Too weak a shaft over-flexes as it leaves the bow, so it kicks tail-out, groups poorly and can strike the rest. It is also a real safety problem, since over-flexing damages the shaft: flex and inspect carbon arrows before every shot and retire any that crackle or show a splinter.