Nock Height

Details

Nock height is measured with a bow square or T-square clipped onto the string at the rest. The square's horizontal arm rests on the arrow rest shelf or launcher, and the measurement is taken from that reference up to the bottom of the nocking point or the bottom knot of the D-loop. A reading of zero means the nocking point is at exact square; positive values mean it sits above square. Most compound archers begin at 1/8" above square as a neutral starting point before consulting paper-tuning results.

The nocking point controls the angle at which the arrow departs the bow. Set it too high and the arrow launches slightly downward at the nock end, producing a nock-high tear in paper. Set it too low and the nock rides above the point, creating a nock-low tear. Because cam geometry varies significantly between bow models, the ideal nock height is not universal — it is determined by the bow's specific cam design, the rest height, and the arrow's dynamic behavior off the launcher. This is why paper tuning is always used to confirm nock height rather than relying on a single published number.

Nock height and rest height are interdependent: raising the rest has the same vertical effect on nock travel as lowering the nocking point. When correcting a nock-high paper tear, most tuners start by raising the rest before moving the nocking point, because rest height is often easier to adjust in small increments and its effect is more direct. Moving the nocking point changes the string angle across the full draw cycle, which can also affect timing and peep rotation on some setups.

Once dialed in, nock height should be recorded and checked periodically. String stretch over the first few hundred shots, D-loop serving compression, and limb set on a new bow can all shift nock height subtly. Re-checking with a bow square at the start of a new season — or after changing strings — catches drift before it affects groups.