Spine is how much an arrow shaft bends. It must match your bow's draw weight, your arrow length and your point weight: too weak and the arrow flexes too much, too stiff and it will not flex enough, and either way groups open up. Find your draw weight and arrow length on the arrow maker's spine chart, then choose the shaft it lists.
The right spine is the difference between arrows that group and arrows that wander, even with a perfect release.
What spine is
Spine measures how much a shaft bends under a standard weight. When you release, every arrow flexes as it leaves the bow. The right spine lets it recover cleanly and fly straight.
What changes the spine you need
| Factor | Effect |
|---|---|
| Higher draw weight | Needs a stiffer shaft |
| Longer arrow | Acts weaker |
| Heavier point | Acts weaker |
| Compound with fast cams | Often needs stiffer arrows |
| Release aid vs fingers | Changes how the arrow flexes |
Reading a spine chart
- Find your draw weight (or peak weight for compounds).
- Find your arrow length, measured to the maker’s standard.
- Choose your point weight.
- The chart shows the recommended spine.
When you sit between two spines, a pro shop can help you choose.
Arrow length
Arrows are cut to suit your draw length and rest position, leaving safe clearance past the rest.
Choose your bow type with our compound vs recurve guide, and set up a safe backyard target. Browse arrows and points.
Common questions
Does a lower spine number mean stiffer?
For most carbon arrows, yes. A 300 spine is stiffer than a 500 spine. Some makers use other systems, so check the chart for that brand.
How does point weight affect spine?
A heavier point makes the arrow act weaker. A lighter point makes it act stiffer.
What is GPI?
Grains per inch: the shaft weight. Total arrow weight (shaft, insert, point, nock and fletching) affects speed, kinetic energy and noise.
Do I need different arrows for hunting?
Hunting arrows are usually heavier, with broadheads instead of field points. Check that broadheads and field points fly together after tuning.