Arrow setup analysis for a 32-inch arrow at 320 fps. Default specs: 415 gr arrow, 8.4 mm shaft diameter.
Total arrow mass for a 32" build: 415 gr = 272 gr shaft (8.5 GPI × 32") + 143 gr components (point + insert + nock + fletching).
KE: 94.4 ft·lbf — Momentum: 0.590 slug·ft/s
| Distance | Velocity | KE (ft·lbf) | Momentum (slug) |
|---|---|---|---|
| 0 yd | 320.0 fps | 94.4 ft·lbf | 0.590 |
| 10 yd | 314.5 fps | 91.2 ft·lbf | 0.580 |
| 20 yd | 309.1 fps | 88.1 ft·lbf | 0.570 |
| 30 yd | 303.8 fps | 85.1 ft·lbf | 0.560 |
| 40 yd | 298.6 fps | 82.2 ft·lbf | 0.550 |
| 50 yd | 293.5 fps | 79.4 ft·lbf | 0.541 |
This build pairs a long cut with a high-speed compound launch. At 32 inches the shaft is favoured by tall archers and long-draw target shooters who want maximum stability and momentum, and 320 fps is the kind of speed produced by aggressive, high-let-off compounds built for flat trajectories and short reaction windows. Together they finish at about 415 grains, which is what drives the kinetic energy and momentum figures in the table above.
Because this is a long cut, a long shaft flexes more under launch, so the dynamic spine reads weak and a stiffer static spine compensates. The launch matters too: with a high-speed compound launch, the dynamic-spine reaction is dominated by spine and rest tuning, because fast cams expose the smallest paper-tear and broadhead-flight errors. Pick a static spine that lands stiff once this 32" shaft and your point weight are factored in, then confirm it with bare-shaft or paper tuning.
At roughly 94.4 ft·lbf this is elk-class kinetic energy — this reaches elk-class energy, the territory recommended for elk, moose, and other heavy big game where maximum penetration is the priority. Keep in mind that a long cut at 320 fps is only the starting point; broadhead choice and shot placement still decide the outcome more than the headline energy number.
A high-speed compound launch pushing roughly 415 grains yields about 0.590 slug·ft/s of momentum. That is maximum penetration potential: momentum is at the maximum end, delivering the deep, bone-crushing penetration sought for the largest game and the steepest quartering angles. Momentum, more than raw kinetic energy, predicts how a 32" arrow holds up against bone and angled entry.
For a long cut launched at 320 fps, dial in rest centre-shot and timing first, then verify broadhead flight against field points at distance. Spine and rest tuning, because fast cams expose the smallest paper-tear and broadhead-flight errors — so re-check the tear any time you change point weight, since that shifts the dynamic spine on a 32" shaft more than most archers expect.