What is a good FOC %?


Squirrelhunter91

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What is a good FOC to have? I just calculated mine using this calculator:

http://home.att.net/~sajackson/archery.html (THANKS HUTCHIES!!!)

According to the above calculator, I have an FOC of 8%. Is this good enough for deer, bear and turkeys? This is with a 100gr tip, If I switched to a 125 grain tip, my FOC would increase, correct?

Here are the specs of my arrow:

Raw shaft- 218.05 gr

Nock- 24.7 gr

Fletch & Wrap- 26.2 gr

Insert- 16.9 gr

Broadhead- 100 gr

The length of my arrow from nock to tip of field point is 25 5/16".

If anyone has that archers software and wouldn't mind putting my specs through it, I'd appreciate it. If you need any other info about my setup, just ask me!!

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Re: What is a good FOC %?

FOC is just a percentage based on the arrows center of gravity. There is no set optimum FOC for all arrows. Calculating it only gives you a rough idea of what it will be. The only way to get at the real value is to measure it yourself.

In my experience the less your total arrow weight is the more your FOC needs to be. If you're at a minimum weight arrow you need the maximum FOC.

Arrow spine is inversely related to FOC. Increase FOC and arrow spine goes down. Decrease FOC and arrow spine goes up. This means ANYTHING you do to an arrow that changes FOC changes your effective spine some.

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Re: What is a good FOC %?

A good range for compunds is 8% to around 15% so your ok.

Like Leo said FOC and spine rating is related hand and hand but using carbon arrows with such a wide spine rating makes it much easier to play with length and tip weight to achieve faster flight.

Not that its best to do that but I am just making a pont that its not unsafe to do so.

The shorter they are the stiffer they will become but since a compound has true center shot its not that much of an issue.

For traditional bow, who require flex (archers paradox) to clear the riser and then restabilize beyond the bow, spine a major issue. This is also why you will see some trad arrow sporting 200g to 300g tips and shooting logs. LOL

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Re: What is a good FOC %?

My only advice would be to not worry about FOC % and just make sure you're shooting tight groups.

When you send a sell placed arrow through a deer's vitals, I'm pretty sure he's not going to look at you and say "your FOC % is way off pally." wink.gif

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Re: What is a good FOC %?

ok here what my Archers Advantage program says.

i plugged in these numbers.

raw shaft lenght..24.5 at 8.9 grs per and 218.05 total weight.

nock 24.7 grs

fletch and wrap 26.2 i just divided by 3 and got 8.7 grs per fletch.thats with your wrap in there.

insert 16.9

point 100grs.

total arrow weight is 384.9 FOC 8.8 which i have to say is low for a hunting arrow. i added a 125 gr point and the FOC came to 11.4 with total arrow weight at 409.9 that is really good in my book.

i like FOC on hunting arrows over 10.0 again you will lose a little speed on the extra 25 grs if you add the 125 gr tip. but it will only be minute.. like 5 fps. but you gain a huge amount of stability on the arrow you have.

the reason your arrows FOC is way put of whack is that 24.7 gr nock and the fletch and wrap 26.2. thats a lot of weight on the flecth end of the arrow with a light tip like the 100gr.

once you FOC is determined , then you need to shoot these arrows. im betting they will group better with the heavier tips. im sure this will also help in the accuracy deparment.

i spend hours on my arrows, making them just perfect for my broadheads. i want the buisness end of my shot to be the most accurate it can be.

Shoot Strong

Tony

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