FOC
#5
Giant Nontypical
Join Date: Feb 2003
Posts: 9,175
RE: FOC
F.O.C. = Front Of Center
Measure the length of your arrow from the front of the insert to the bottom of the notch in the nock.
Divide that by 2.
Find the balance point of your arrow.
Measure from the bottom of the nock to the balance point.
Subtract 1/2 arrow length from the measurement to the balance point.
Divide that by the arrow length
Multiply by 100 = FOC %
For instance, my arrow is 32" long.
1/2 that is 16"
Balance point measures 20" from the nock.
20-16 = 4
4/32 = 0.125
0.125 X 100 = 12.5
FOC on that arrow is 12.5%
Or go online, Google up 'Archery FOC calculator'and use one of the myriad FOC calculators out there. but expect different results with different calculators because not everyone actually agrees on how to measure FOC. Some folks insist the only proper way is to include the length of the point in the overall length measurement. The way I described is AMO standard.
Measure the length of your arrow from the front of the insert to the bottom of the notch in the nock.
Divide that by 2.
Find the balance point of your arrow.
Measure from the bottom of the nock to the balance point.
Subtract 1/2 arrow length from the measurement to the balance point.
Divide that by the arrow length
Multiply by 100 = FOC %
For instance, my arrow is 32" long.
1/2 that is 16"
Balance point measures 20" from the nock.
20-16 = 4
4/32 = 0.125
0.125 X 100 = 12.5
FOC on that arrow is 12.5%
Or go online, Google up 'Archery FOC calculator'and use one of the myriad FOC calculators out there. but expect different results with different calculators because not everyone actually agrees on how to measure FOC. Some folks insist the only proper way is to include the length of the point in the overall length measurement. The way I described is AMO standard.
#6
Typical Buck
Join Date: Feb 2003
Location: Nebraska
Posts: 760
RE: FOC
Never seen it done like that Arthur but it works. Another way of doing it is you do the first steps as Arthur stated . Measure what the difference from your balance point to arrow center, Take that dimensions times 100 and then divide that number by the total length of your arrow. We will use Arthurs numbers . 32 inch arrow halfway is 16 balance point is 4 inches from center. 4 times 100 = 400
400 divided by 32(total length of arrow) =12.5 % FOC
400 divided by 32(total length of arrow) =12.5 % FOC