What is FOC???
 

What is FOC? What does FOC do? Is a higher number better than a lower number FOC? What is a good FOC? All I know is what it stands for and it's really buggin' me for some reason. [>:]

RE: What is FOC???
 

FOC stands for Front Of Center.

For fixed blade broadheads I like to keep my FOC around 12%.

RE: What is FOC???
 

So is 11% better than 12%? Or is it situational? Very confused. [:@]

RE: What is FOC???
 

FOC means Front of center or forward of center.

It is the point on your completely fletched and set up arrow shaft where it will balance.

Recommended is bewteen 10 and 12%.

RE: What is FOC???
 

9% is Ideal forward of Center
here is the most accurate way to determine forward of center...

Get a long finishing nail and nail it into a wall just enough to get it snug without falling out. Now with your finished arrow find the balancing point on the arrow and mark that spot on the arrow.

Measure from the throat of the nock to the end of the shaft ( do not measure the point or insert) this is the cut length of your arrow.

Now, divide this measurement by 2 this will give your center of the arrow measurement.

Mark the center of the arrow (from the throat of the nock to the center).

Measure the distance between the balancing point to the center.

Multiply this measurement by 100 then divide that multiple by the arrows cut length.

This will give you your FOC%

RE: What is FOC???
 

For the Overly Concerned!;)

RE: What is FOC???
 

For Optimal Contengentcy

RE: What is FOC???
 

Fussing Over Crap

RE: What is FOC???
 

Reading the responses it would appear there is some disagreement on the ideal FOC--ie--9 v. 12. Can someone explain in practical terms how and why a 12 FOC is better than a 9FOC or vice versa? Does the speed the arrow is flying make a difference? My present setup is 10+--I'm contemplating a broadhead change that would change it to a 9. What practical difference does it make? Would I be correct in assuming that the only true test is how broad heads actually fly. Thanks in advance.

RE: What is FOC???
 

Well, I don't have a clue where that "9% is optimal" stuff came from. Everything I've ever seen suggests a range from 10-12%.

If you add, "under less than perfect conditions", that's totally, absolutely, 100% correct.

RE: What is FOC???
 

I shoot a lot of Field archer that consists of shooting fistances of 80 + meters and 9% will carry the arrow further with less drop rate
12% is Good FOC % but I preferr as close to 9% as I can get.
that is just me
I am arrow flight anal[8D]

RE: What is FOC???
 

I've seen numbers as high 15% suggested. And not every one measures FOC the same either, there seems to be a dissagreement on which is correct. My feeling is that 9% would be a bit on the low end for a hunting set up. Not that it couldn't be done though. And we need to keep in mind that Bigpapa shoots pretty light arrows as well, not to mention his bow is most likely tuned very well.

I don't beleive there is an optimum value. Like everything else in archery it really depends on your set up. The type of head you shoot, length of your arrow, weight of your arrow, spine of your arrow, type of fletching you shoot and how well your bow is tuned will all play a part in your FOC.

Some would have trouble getting as low as 9% FOC with a conventional set up, for others it would be the other way around.

Basically what FOC does is cause the nose of your arrow to want to go down in flight. This would in turn cause your tail to go up forcing your flethchings to control the arrow more. Too much FOC hurts your trajectory, too little could make your arrow unstable and unforgiving. A large arrowdynamically challenged head may require more FOC and better fletching to fly well.

The point is to not go real light on foc if you are going to shoot a fixed blade head. 9% would work if you had good spine and a well tuned bow. I have done it with less. I have also shot with 16% and had no problems either.

And the point some of the others are trying to make is that it is about the last thing most of us consider. More important would be spine in my opinion. And if you changed to a heavier tip or lighter fletch to get more foc and your arrow flew better, who is to say it was the FOC, or the fact that you may have changed your spine for the better?

Most common arrow set ups will yeild plenty of FOC, so I wouldn't fret over it. And you can go to Bowjacksons site and it will figure your foc with different components to see what you have or what you could get.

http://home.att.net/~sajackson/archery.html


At least that is my opinion on FOC. Nobody is really right or wrong on this issue, it's just what works best for them in most cases.

Paul

RE: What is FOC???
 

I figgered as much... target arrows with nibbs or field points. Problem is, the question was asked about broadheads. ;) I'm arrow flight anal as well, especially with broadhead tipped hunting arrows, and consider stability over hunting distances to be far more important than 80 yard trajectory. Higher FOC = more stability. More stability = better accuracy, easier tuning, more forgiveness in adverse hunting conditions. At least for us mere mortals.

RE: What is FOC???
 

Ya, I was thinking that was kind of high for field archery actually. Don't some of those like 5 or 6 percent? Of course most of them don't use inserts either, just target points.

Paul

RE: What is FOC???
 

Although I'm sure this statement is true, I've never found it to mean much at hunting distances. I've shot 15% and compared it to 12% and couldn't detect any significant difference inside of 30 yards. It can be difficult to find a broadhead/arrow combination that will weigh the same, yet give large differences in F.O.C. It's a natural result of increasing FOC, to have a greater arrow weight. This as much as anything is what hurts trajectory inside of 30 yards, and even that isn't much concern unless the arrow is real heavy.

I would probably add - with no wind and no twigs or grass possibly in the way.

Although I don't find a particular FOC that is best, I do find that the higher the number the better arrow flight is. Few people have to worry about getting too high. It's difficult to walk into many bow shops these days and even find a broadhead that weighs over 160 grains. I did a little informal survey of the guys in my winter league and asked what grain broadhead they used. I only asked about 25 guys, and out of that number the highest was 125 grains. You would have to be shooting a very low poundage bow with a very light arrow for a 125 gr head to get the FOC over 12 or 13%.

RE: What is FOC???
 

Thanks for the additional explanation. I shoot GT7595s out of bowtech sc patriots. One is set at 71lbs, the other 74lbs. Both bows shoot at between 278-280fps. I have been shooting 100g slick tricks and would like to give the 85's a try. These arrows seem to have more than enough spine and the bows are well tuned. I can't imagine shooting past 50-55yds even under perfect conditions (I turned down a hell of a mule deer this fall at at 70 even though I practice out to 65). My bottam line is I want as stable and accurate arrows as possible so as to have one less variable. My calculations puts 271/2" shafts right at 9%FOC. Any thoughts? I'm assuming I'll have to wait till spring to check out accuracy and arrow flight at longer ranges when the weather permits shooting outdoors.

RE: What is FOC???
 

HEY CONTENDERMAN, JUST GO www.goldtip.com THEY WILL TELL YOU EVERYTHING YOU NEED TO KNOW. AND THEY HAVE A PAGE WHERE YOU CAN ENTER ALL YOUR ARROW INFO AND THEY WILL TELL YOU WHAT THE FOC IS ON YOUR ARROW. MAN I THINK YOU HIT A NERV WITH A FEW FOKS