Flat nock vs Half-moon nock: specs compared
Updated 05 September 2026.
4
specs differ
Flat nock and Half-moon nock differ on 4 specs: nock, form, fits, compatibility rule.
| Spec | Flat nock | Half-moon nock |
|---|---|---|
| Nock | flat (flat-back) nock | half-moon (moon) nock |
| Form | plain flat disc on the shaft base, non-indexed | shallow concave groove across a flat disc; must be indexed to the string |
| Fits | Excalibur Micro series and older recurve crossbows | CenterPoint, most Barnett non-Hyper models, and many entry and mid crossbows |
| Compatibility rule | The flight groove and rail must align the string to the centre of the flat base. Excalibur supplies flat-nocked arrows for the Micro series; it does not require proprietary arrows but cautions against anything under 350 total grains. | The groove must be indexed square to the string on every shot. If the odd-coloured (index) vane is not down, the string can sit on the rim of the nock and dry-fire the bow. |
Questions and answers
How do Flat nock and Half-moon nock compare?
Flat nock and Half-moon nock differ on 4 specs: nock, form, fits, compatibility rule.