FOC, or frontal of center, is a measurement of how balanced an arrow is. The further back the weight is concentrated, the higher the FOC.
A higher FOC generally results in more stable flight and penetration power. For hunters, this means that arrows with a higher FOC are more likely to result in a successful kill. But is it always so? Let's find out.
What is FOC?
FOC is the percentage of an arrow's weight that is located in front of its center of gravity. In other words, it's a measure of how "front-heavy" an arrow is.
It describes the arrow's balance point, or where the center of gravity is located in relation to the total length of the arrow. The higher the FOC, the closer the center of gravity is to the front of the arrow. A higher FOC can result in increased accuracy, penetration, and kinetic energy transfer.
Why Does FOC Matter?
A front-heavy arrow will be more resistant to wind drift than a rear-heavy arrow. This is because the wind will push against the heavier front end of the arrow more than the lighter rear end. As a result, a front-heavy arrow will be less affected by crosswinds and will stay on target better than a rear-heavy arrow.
Another reason why FOC matters is that it affects an arrow's trajectory. A front-heavy arrow will have a flatter trajectory than a rear-heavy arrow because it will retain more velocity as it flies through the air. This can be especially helpful when hunting at long range, as it minimizes the need for precise elevation adjustments.
Finally, FOC affects an arrow's kinetic energy and penetration potential. All things being equal, a front-heavy arrow will pack more punch than a rear-heavy arrow because it will transfer more energy to its target upon impact. This can be critical when hunting large game animals like elk or moose, as you'll need all the penetration power you can get to ensure a clean kill.
However, an arrow with a high FOC can be very difficult to shoot accurately. A high FOC can cause an arrow to fly erratically and makes it more difficult to stay on target.
How Is FOC Measured?
1. Calculate the actual length of the arrow, which is the distance from the nock groove to the tip of the arrow shaft (include the insert if you have any). But don't include the length of your broadhead.
2. Divide the length you found in step 1 by 2. This is the exact center of your arrow.
3. Find any fulcrum and place your arrow to balance it perfectly. This is the balance point of your arrow and it will depend on all the components attached to your arrow. Mark this balance point.
4. Measure the distance of the balance point you calculated in step 3 from the bottom of the nock groove.
5. Subtract and find the distance between the balance point (from step 4) and the center of the arrow (from step 2).
6. Express this number from step 5 as a percentage of the length of the arrow from step 1. You will get your FOC which is expressed as a percentage.
Ideal FOC of an Arrow and Changing its Value
The ideal FOC for an arrow is typically between 10-15%, but this will vary depending on its usage. A higher FOC results in a “heavier” feeling arrow and can help to increase accuracy.
There are several ways to change the FOC of an arrow, and the easiest way to change the FOC of an arrow is to alter the weight distribution. This can be done by adding weight to the tip of the arrow, changing your broadhead, inserting point weights, using arrow sleeves, or shifting the position of the vanes. Another option is to use different types of arrows, such as those with heavier heads or those with aerodynamic shapes.
Finally, the length of the arrow can also be changed in order to alter the FOC. By experiment and trial and error, every archer will eventually find an ideal FOC for their equipment and shooting style.
Check out thehelpful video for more details:
What is a Good FOC for a Hunting Arrow
Generally speaking, a FOC percentage that is around 10 to 15 percent is considered a standard. For target shooting, it can be lower and a 7% to 10% range would be sufficient. Even for practice shooting and archers, FOC barely exceeds 15%.
But for a hunting arrow, it depends on the game you are hunting. Big, heavily-muscled animals like elk and moose need a heavier arrow, with a FOC of 18% - 22% that will have more kinetic energy to penetrate their hide and flesh. Smaller animals like deer can be taken down with a lighter arrow with less kinetic energy and a FOC value under 18%. For even bigger animals, like bears or maybe even an elephant FOC as high as 30% would be necessary.
When choosing a hunting arrow, make sure to pick one that has the right FOC for the game you are planning to hunt. A too-light arrow will not have enough kinetic energy to take down a big animal, while a too-heavy arrow will be difficult to handle and less accurate.
The best way to find an ideal FOC for your hunting needs is to experiment with different weights and configurations until you find one that works best for you.
A well-balanced arrow is crucial for successful hunting. That's why it's important to pay attention to an arrow's FOC. By understanding what FOC is and how it affects an arrow's flight, you can choose arrows that are more likely to result in a successful kill shot.
And if you are in the market for a great set of hunting arrows, then our selection is perfect for you. We did the research for you and only choose arrows that are top-quality and perfect for hunters of all experience levels.
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