What is arrow weight?

As the name suggests, arrow weight is the overall weight of your arrow. This includes all components of the including the arrow shaft, flights, nock, insert, and broadhead. Unlike other small scale weight measurements, arrow weight is measured in “grains” (grs) and not grams (g). For a quick point of reference, 15.43 grains will equal 1 gram in weight.

Why does it matter?

Arrow weight is used to determine arrow speed, kinetic energy, and momentum. These factors will allow you to determine the flight characteristics of your arrow, and the suitability for hunting different game species. As a general rule, a lighter arrow will travel faster, have a smoother trajectory, and produce tighter groupings. A heavier arrow will have more kinetic energy and momentum, which is less prone to disruption by environmental factors, and will achieve greater penetration on your target animal. When building an arrow, a balance must be struck between these two values to optimise your arrows performance.

What constitutes a light, medium, or heavy arrow?

The answer to this question will change, depending on who you ask. For the sake of this guide, I will say that anything less than 400grs is a lightweight arrow, between 400 and 450grs will be a medium weight arrow, and anything beyond 450grs is a heavy weight arrow.

Note: Archers should avoid hunting medium or large game animals with an arrows weight under 380 grains. This is due to lack of kinetic energy, and momentum.

Characteristics of a heavy arrow

A heavy arrow will absorb more of the bow’s kinetic energy, this will produce:

• Slower arrow speed,
• Deeper penetration,
• Better resistance to cross-winds, rain, and snowfall, and;
• A quieter shot.

Characteristics of a light arrow 

A light arrow will absorb less of the bow’s kinetic energy, this will produce:

• Faster arrow speed.
• Increased flight stability,
• A smoother flight trajectory (i.e. less drop).
• Less resistance to environmental factors, and;
• An arrow that may be slightly more difficult to tune.