Arrow Speed Fundamentals
Arrow speed depends on the energy stored in the bow at full draw, the efficiency of energy transfer from the bow limbs to the arrow, and the arrow mass. Heavier arrows fly slower but carry more momentum, while lighter arrows fly faster with less kinetic energy. Compound bows typically achieve 80-85% efficiency, while traditional recurve bows are around 70-75%.
Arrow speed is one of the most important ballistic parameters for archers and bowhunters. Faster arrows have flatter trajectories, reducing the need for range estimation. However, momentum (mass times velocity) is what determines penetration on game animals, so there is always a trade-off between speed and arrow weight.
Energy Transfer Formula
The stored energy is the potential energy in the bow limbs at full draw. After accounting for energy lost to limb vibration, string oscillation, and noise, the remaining kinetic energy accelerates the arrow.
Typical Arrow Speeds
| Bow Type | Draw Weight | Arrow Weight | Speed (fps) |
|---|---|---|---|
| Compound (hunting) | 70 lbs | 400 gr | 280-310 |
| Compound (target) | 50 lbs | 350 gr | 250-270 |
| Recurve | 45 lbs | 450 gr | 170-190 |
| Longbow | 50 lbs | 500 gr | 150-170 |
FAQ
What is the minimum arrow weight?
The general rule is a minimum of 5 grains per pound of draw weight. For a 60 lb bow, that is 300 grains minimum. Shooting lighter arrows is called dry-firing and can damage the bow because excess energy stays in the limbs. Most manufacturers recommend 6-8 grains per pound.
Does arrow speed affect accuracy?
Faster arrows have flatter trajectories, reducing errors from range estimation. However, lighter arrows for speed are more affected by wind drift. The best accuracy comes from finding the right balance of speed, weight, and spine stiffness for your specific bow setup.
How is IBO speed measured?
The International Bowhunting Organization (IBO) standard measures speed at 70 lb draw weight, 30 inches draw length, and 350 grain arrow weight. This provides a standardized comparison between bows. Actual hunting speeds are typically 20-40 fps slower due to heavier arrows and shorter draw lengths.