Arrow spine for a 45 lb compound at a 28 inch arrow with a 100 grain point: a 500 spine (band 500-600), plus the 225 grain minimum weight. Sourced.

Updated 05 September 2026.

Arrow spine by setup · bolt datasheet

What arrow spine for 45 lb draw at a 28 inch arrow

The starting spine for a 45 lb draw at a 28 inch arrow with a 100 grain point, and the weight floor.

For a 45 lb draw at a 28 inch arrow with a 100 grain point, start with a 500 spine (the 500-600 band), and keep the finished arrow at or above 225 grains total.

This setupmanufacturer data, cited

Draw weight	45 lb
Arrow length	28 in (cut, nock groove to shaft end)
Point weight	100 gr
Recommended spine	500 (published band 500-600)
Minimum total weight	225 gr, from the 5-grains-per-pound floor

A shaft in this spine

Easton 5mm Axis carbon arrow shaft (500 spine)

Shop Easton 5mm Axis carbon arrow shaft (500 spine) on Amazonaffiliate Find Easton 5mm Axis carbon arrow shaft (500 spine) on eBayaffiliate

Field notes

A 45 lb draw at a 28 inch arrow with a 100 grain point takes a 500 spine, the top of the light band. It is a common youth-to-adult transition setup on a compound.

Spine is a starting point, not a guarantee, because a 340 from one brand can differ from another. Confirm on your arrow maker's chart at 28 inches and 45 pounds, or bare-shaft test before cutting a dozen.

Whatever spine you land on, keep the finished arrow at or above 225 grains total, the 5-grains-per-pound floor, so the bow is not shooting dangerously light.

The rules behind this pick

What an arrow spine number meanswhy this spine The arrow-length rulewhy length changed it Easton 5mm Axis spine charta shaft offering the 500 spine Easton 5mm Axisits full spec The 5-grains-per-pound floorminimum 225 gr here

Questions and answers

What arrow spine for 45 lb draw at a 28 inch arrow?

For a 45 lb draw at a 28 inch arrow with a 100 grain point, start with a 500 spine (the 500-600 band), and keep the finished arrow at or above 225 grains total.