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FOC calculator header image

FOC Calculator | Easily find Front-Of-Center of your hunting arrows

If you already know the length and balancing point of your arrow, you can use the FOC Calculator below to quickly find the % of your arrow’s weight that is Front-Of-Center! (enter a number or slide the orange dots to the desired number)

FOC (Front Of Center) | Calculator
Arrow length from end of arrow shaft to the bottom of the nock groove (L)
inches
Distance from balance point to the bottom of the nock groove (A)
inches
FOC (Front Of Center):

0 %

You may have heard other bowhunters talk about the “FOC” of their hunting arrows. (Who knows, you may have even heard “The Ranch Fairy” ranting about high FOC).

But, what does “FOC” mean and how can you easily calculate it?

What does FOC stand for?

“FOC” stands for Front-Of-Center (Or Forward-Of-Center) and refers to the percentage of an arrow’s overall weight that is forward of the balancing point, or, “center” of the arrow.



How to calculate FOC using a formula

You might like the FOC calculator but also want to learn how to calculate FOC using a formula.

The formula to calculate an arrow’s FOC is:

100 x (Balance Point measurement [A] – Arrow Length [L]) / 2.

To use this formula, you will first need to measure the arrow’s overall length as well as finding the balance point measurement.

foc equation graphic
Once you have found the arrow length (A) and balance point (B) measurements, use the formula above to find the FOC of your hunting arrow.

Finding the arrow’s length

To find your arrow’s length for the purposes of calculating FOC, you need to be sure you measure correctly.

Measure your arrow from the end of the arrow (where the broadhead/point screws in) to the bottom of the throat of the nock (see diagram above).

Once you have your arrow length measurement, you need to measure the balancing point…

How to find the “balance point” of an arrow

To find the balance point of your hunting arrow, first be sure you have already installed your nocks, vanes, inserts and broadheads/points onto your arrow.

balance point FOC diagram
To calculate FOC, you first need to find the “balance point” of your hunting arrow.


Using a triangular block of wood, find the exact place that your arrow balances perfectly. (If you don’t have a triangular block, you can also balance the arrow on your finger).

Once you have found the balance point of your arrow, measure from that point to the throat of your nock. This will be your balance point measurement.




tuffhead broadheads
Consider heavier broadheads when seeking a higher FOC.

Conclusion

Once you have measured your arrow’s length and balancing point, you can use the formula provided in the diagram above to calculate the FOC of your arrow.

Certainly bowhunters want to be the best they can be so that they can get an ethical kill. But, when it comes to FOC, there are varying opinions on whether higher or lower FOC is better.

Some bowhunters want an arrow with a lower FOC so that the arrow is as fast as possible. The intent is often to keep the deer or game from “ducking the string.”

Others want an arrow that has a higher FOC %, (you may have seen The Ranch Fairy discuss this) so that the arrow hits the animal with a heavier impact. This tends to increase the odds of a “pass-through” shot.

This can be helpful to increase the chances of a mortal wound in the event you encounter bone or other stiff tissue that might impede the arrows progress.

Hopefully you find our FOC calculator helpful and we hope you have an arrow that’s Just Pass’N Through!

long range rifle on shooting range

Shoot For the Moon: Tips for Long-Range Shooting

Whether you just got your first rifle, grew tired of handguns at the range, or want to be a serious marksman, being able to shoot down-range takes a different skill set. Luckily, there are a few pointers that may help you take on the challenge of long-distance shooting.

Choose Your Rifle Optic Carefully

After the rifle, your biggest decision to make when it comes to long-range shooting is which optic to use. Some factors to consider are magnification, lens clarity, and parallax adjustment,

Whatever your decision, make sure to choose the best long-range optic for you. When you mount it on your scope, be sure to give yourself enough eye relief for the recoil.

Divide By Zero

Once you’ve picked your optic and mounted it properly, it’s important to zero your scope for the distance you’ll be shooting at. Hitting a long-distance target comes down to inches, so accuracy is key.

Zeroing your optic will give you that accuracy and allow you to hit what you aim at consistently. A good range to zero for is 300 yards in the beginning, because it gives a better ground for long-distance situations without being affected by the drop and weather that 500 yards causes.

target showing through rifle scope

Zeroing your rifle at 300 yards will help you once drop and weather that affects the shot more heavily at distances of 500 yards.

Check Your Posture and Breathe Easy

Your shooting stance can impact your shooting ability significantly, whether you fire prone or kneeling. One effective position was used by American snipers in Vietnam, in which you sit on the ground with one knee up and the other leg tucked underneath.

Every shooter has a stance that works for them, so find one that you’re most comfortable with. Remember to keep the stock of your rifle tucked tightly into the meat of your shoulder.

Also keep in mind that there’s a main vein where your stock is, so controlled breathing is essential. For long shots, exhale, wait for your heart rate to slow, and remain still before squeezing the trigger.




Consistency In Shooting Is key

One of the biggest separations between shooters is commitment to a routine. Especially in the beginning, the transition to long-range shooting is hard work.

Mental toughness means practicing often and shooting in tight groups frequently. Muscle memory can help with breathing habits, trigger tension, and reloading.

long range rifle target

When shooting long distances, consistent practice is key, helping to build muscle memory.

Study and Learn

The longer the shot, the more factors will affect the bullet. Over a distance of 300-500 yards, you’ll experience bullet drop and wind.

If the target is moving, you might have to calculate your bullet’s time to target and adjust. The average shooter won’t deal as much with this, but hunters and snipers will.

As you continue to shoot longer distances, you’ll pick up tips that you take with you, like what grain of bullet has the best velocity for your needs.



Be Patient

hunter shooting a rifle

The ability to be still is critical when shooting a rifle long distances. Individuals who hunt deer and other big game certainly know the importance of staying still and quiet.

When you take a long shot, your body needs to be still. For snipers and some hunters, the ability to be quiet and unmoving is one of the biggest assets.

Even for the average long-distance shooter, though, patience is important. Expert marksmanship takes time and practice, so don’t expect to master it overnight.

Experienced riflemen can take years to reach their level of shooting. Zero your optic, work on your routine, and continue to practice.



Keep Your Rifle “Safe”

One important aspect for long-distance shooting is your routine afterward. After you clean your weapon, what do you do?

You might need to wipe off the lenses of your scope and place the lens caps, but taking care of your rifle makes a difference. Dust or dirt can affect accuracy and rifling, so you should invest in a gun safe to keep your weapon clean and protected between shoots.



Final thoughts on long range shooting tips

So, whether you are a novice or an expert marksman at long distances, these 6 tips should help you hone your craft at long-range shooting. Let’s review one more time:

  1. Choose the right long range optic
  2. Zero your rifle
  3. Practice proper posture and breathing
  4. Consistently practice your shooting routine
  5. Keep studying and learning
  6. Keep rifle clean and protected between shoots



view while sighting in riflescope view
Richard Dougleas of Scopes Field
ranch fairy holding high foc arrows

High FOC In Bowhunting | It’s About Impact

Trust me, I am not trying to cause a problem with all this heavy arrow stuff.

I was failing.

The Ranch Fairy and promotion of high FOC (Front of Center) arrow systems began because of failure at impact. 

High FOC Arrows | How and why they began to matter

Ok, so here’s the abridged version of how and why high FOC arrows became so important to me.  

I really like fishing, bowhunting, and shotguns.  (Of course, after 30 years of marriage – and still going – Mrs. Fowler is awesome too). 

So anyway, I killed a 150” deer in 2009 and just lost interest for “deer” hunting.  I became an adult along the way (which surprised me too), had kids, and helped them become quite competent adults and outdoors folks.

ranch fairy troy fowler with dead hog and iron will broadhead

Do you want exit wound when encountering humerus breaks, shoulder blades, and spinal columns? High FOC is the answer.

I did NOT, however, lose my love for hunting mature, feral hog boars.  They are every bit as challenging as a cagey whitetail, with additional features. Mostly, they suck up arrows like a vacuum and run off laughing. 

When you ask the guys at the local shop why they get away so often, they say something like, “big boars are just tough.” 

That’s it?  Just keep trying what you’ve got?  We don’t know anything else but “shoot fast and shoot a mechanical, ’cause they make huge holes?”

I was doing both (plus some fixed blades… guess we aren’t supposed to admit that!)  



FOC stands for “Front Of Center” (or Forward of Center), which indicates what percentage of the overall arrow weight is in front of the balancing point, or “center” of the arrow.

I nearly quit bowhunting

At one time, I was below a 50% kill rate on big boar hogs. And bro’, I live in Texas… we use bait, and shoot at known distances! 

Still, 90% of the pigs I killed (or lost) had 12 or more inches of arrow sticking out of them.  

There were poor blood trails, long nights, and lots of magically disappearing pigs. 

So, I almost quit bowhunting the big pigs.  I mean, I have guns.  After all, they are, as my buddy Chris says, “very efficient”.  

Enter one Dr. Ed Ashby and his incredibly in-depth Natal Study. 



Ed Ashby to the rescue

In his Natal Study, Ed Ashby identified 12 arrow penetration enhancing factors (visit www.ashbybowhunting.org for more information). 

I start reading and my mind starts melting!

He’s preaching: structural integrity, perfect arrow flight, rigid one piece single bevel broadheads, 350 grain points and inserts…..650 grain arrows?

ARE YOU KIDDING?

ed ashby with an archery asiatic buffalo

Dr. Ed Ashby, here with an asiatic buffalo, stresses the importance of structural integrity and perfect arrow flight.

I had no other thing to try. The archery shop “dock talk” wasn’t working.  

Now, this is not a popular thing, circa 2013. I mean, it’s completely irrational, right?

Except Ed was regularly killing Asiatic buffalo, including exit holes, and he had a couple rhino’s, with a bow, as a kicker. 

Oh, and just to check the man card, he used traditional gear. (That’s right, longbow, recurve, etc).

So, I jumped off the bridge with high FOC arrow builds and never looked back.  What did I have to lose?

Fast forward 7 years and hindsight being what it is, bowhunting is very simple… bowhunting is 100% equivalent to what happens at impact.

And, how much penetration your arrow achieves will increase your success; not the bow, stabilizer, or whiz bang back tension release, or a miracle peep sight. 

The broadhead and arrow kill the animal. 

Which one is best?  Let’s move on.

Murphy’s Law (Anything that can go wrong will go wrong) certainly applies to bowhunting. But, what if we could have things go RIGHT more often?

What is a high FOC arrow?

So, Fowler “land the plane man!”  Get on with it… “what is a high FOC arrow?” 

Now, before we continue, you must realize that FOC or “front of center” is the measure of how much total arrow mass is in the front.  The industry says 8-12% FOC is normal. 

A high FOC arrow starts around 15% and can go up to 30%.

Just as a comparison, we are talking about 100 grain points vs 300-350 grain points. 

So, I’d agree wholeheartedly that 8-12% is normal FOC.  But that doesn’t answer a simple bowhunting question.  “Is that the optimal arrow FOC from bow to animal i.e., “in flight” or is it the optimal arrow FOC to get through the deer, hog or other animal?” 

The industry just leaves that as an assumption while moving on to bow tuning and other shenanigans.

How to calculate the FOC of an arrow

To determine the front of center (FOC) of your arrow, first install the inserts, points/broadheads, wraps, vanes, nocks, etc that you will be using on the arrow shaft. Once you have completed your arrow setup use the equation in the graphic below: 

foc equation graphic
  1. Divide the length of the arrow (indicated by “L” in the graphic above) by 2.
  2. Find the balance point. (The balance point is where the arrow balances perfectly on your finger or other object). Mark the balance point and measure the distance from that point to the bottom of the groove of the nock (this distance = “A” in graphic above).
  3. Subtract center of the arrow measurement (calculated in step 1) from the balance point measurement (calculated in step 2).
  4. Multiply the result from step 3 by 100.
  5. Divide the result from Step 4 by the arrow’s overall length (L). This result will be the FOC of your arrow.

FOC Calculator

If you don’t want to take the time to do the math to find your arrow’s FOC, you can always use an FOC calculator. Just be sure your arrow has the inserts, points/broadheads, wraps, vanes, nocks already installed.

The benefits of high FOC arrows

Before we jump off the FOC bridge, let’s clarify some things. 

  • Ashby Rule #1 – Structural Integrity: The arrow and broadhead system cannot fail, bend, or redirect at impact. 
  • Rule #2 – Arrow Flight: Perfect arrow flight is the enabler to penetration, when rule #1 is achieved. 

Structural integrity

Just so you know, I bare shaft tune each individual arrow before fletching, using the point weight I want to achieve for higher FOC.  I suggest you do the same. 

High FOC arrows often carry 300+ grain point or point / insert systems.  This places a tremendous amount of impact energy into a very small area, pulling the arrow into the target. 

high foc field points

Heavier inserts and field points/broadheads will help increase your arrow’s FOC.

Think of it like this.  You’re shooting a 300-grain bullet with a tail.  With lower FOC, you have a long object pushing a light point into sinew, meat, and bone. 

It’s like hitting a nail with a hammer. 

So, if you miss-hit the nail a little and your “arrow” goes sideways – it kills penetration. 

But, what if we could pull the nail into the board?  (Structural integrity, perfect flight assumed – you have to do that first).



Arrow flight

A second benefit of high FOC arrows is great arrow flight, which increases accuracy. 

During my journey, somewhere around 16% FOC, I started to see much more consistent grouping. It was like I was a better shot.  It just doesn’t take as much concentration on form and grip, etc. 

The heavier points, after proper bare shaft tuning, seem to pull the arrow along, and the fletch is just back there stabilizing the end of the arrow. 

ranch fairy troy fowler with feral hog

Since switching to high FOC arrows, my kill rate on tough feral hogs has gone to nearly 100%.



Better broadhead choice

Finally, the jump to these higher FOC arrow systems almost requires you to buy better broadheads, made of great steel. 

It’s not uncommon to have tool grade steels. The heads are machined, one-piece, and .08 thick. 

They are solid.  No fail points – (Rule #1 – Structural Integeriy… CHECK!)

For the bowhunter, this discussion may seem a bit off the rails. I would agree. The FOC town has an idiot, and I am he. 

However, my pig killing stats have gone to almost 100%.  Literally, if one gets away, I made a non-vital hit, and that’s on me. 

But, the adult arrows don’t fail anymore.  My arrows don’t break, the broadheads don’t bend or dull on impact, and penetration is almost always into the dirt (unless I hit a big off-side bone, which usually breaks, and turns the pig into a three-wheel drive unit. Pigs have short legs, so from an elevated position, its common to hit the ground before it passes through.) 




Conclusion

In closing, I am vitally aware a “normal” arrow system kills millions of critters a year of all sizes. 

Mechanical broadheads, the same.  I got that.  I’ve done it. 

But, what if you had an arrow system you knew, for a fact, was going to achieve an exit wound in the absolute highest number of situations – all  impact side humerus breaks, shoulder blades broken, and spinal columns snapped with almost 100% efficiency?   

What if we accept Mr. Murphy is still alive and well, but we used a tool to level that playing field?  

The next time you see your hunting arrow, you should ask, “Is my arrow system capable of almost any impact point OR only if I have perfect shot placement?”

Bowhunting is 100% equivalent to what happens at impact. And, how much penetration your arrow achieves will increase your success. 

ranch fairy troy fowler holding redfish
Troy Fowler, AKA The Ranch Fairy.

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