FOC Who has actually measured and calculated?

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jakelogsdon

jakelogsdon

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I built some arrows last year and ended up at 16% FOC and 500gr, they don't fly any better or worse than my last arrows that were 390gr with 9% FOC. They hit harder but also are 25% heavier, my next arrow will most likely be back down around 11% FOC so I can go with a more durable arrow and still end up right around 500gr.

Both arrows killed elk equally well.
How far are you shooting?
 

Beendare

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Put me in the don't know and don't care category. I'm in the teens I'm sure.

There for awhile on the archery forums there were many touting 25% plus FOC...not so much anymore.

I think Easton recommends between 9-16%...they have forgotten more about arrows than the internet experts know.

___
 
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jakelogsdon

jakelogsdon

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Put me in the don't know and don't care category. I'm in the teens I'm sure.

There for awhile on the archery forums there were many touting 25% plus FOC...not so much anymore.

I think Easton recommends between 9-16%...they have forgotten more about arrows than the internet experts know.

___
I'm not trying to chunk a yard dart. that extreme FOC is not something I would really entertain anyway. Just curious about bumping mine up a little
 

Trial153

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I stopped calculating it because i couldnt see any practical diffence. I add enough weight to my total weight up to where i want it ...at that pount i stop worrying about it. I would guess i am in the high teens on all my builds right now.
 
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120 yards is my furthest target. I shoot 80 very often.
You could consider adding a second (lower) peep sight to extend your max range. Or lighten up your arrows for long range practice and add weight back for hunting. I enjoy shooting 120+ yds in the backyard but I'm not planning to take a shot at an animal that far so I use the cheap 380 gr arrows I built for Total Archery Challenge last year for long range practice and save my 630 gr arrows for hunting (with a max pin distance of 75 yds). A quick change out of the sight tape and I'm good to go.
 

nphunter

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You could consider adding a second (lower) peep sight to extend your max range. Or lighten up your arrows for long range practice and add weight back for hunting. I enjoy shooting 120+ yds in the backyard but I'm not planning to take a shot at an animal that far so I use the cheap 380 gr arrows I built for Total Archery Challenge last year for long range practice and save my 630 gr arrows for hunting (with a max pin distance of 75 yds). A quick change out of the sight tape and I'm good to go.

Thanks but I can shoot out past 120 already with a 500gr arrow, I don't really feel like I need to shoot any further, I prefer to shoot my hunting arrow year-round for 3D and messing around so I can build confidence with my setup. I was commenting on distances I shoot because I was asked above by JL how far I was shooting after I said I haven't noticed any change in accuracy going from 9-16% FOC.
 

Nate_Beres

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Id like to be able to shoot to 100, but with my current setup My fletchings will make contact with my scope housing if I dial my sight down that far. Id also like to build an arrow with a 13-15% FOC. I'm definitely happy with the performance of this current arrow setup I've built, including broadhead flight, but I'm always messing around with stuff anyway.
Sounds like a true tinkerer to me. If it ain't broke... Maybe I can make it better.
As a tinkerer myself I've played with FOC.
I've got light arrows, gt velocity, and have played with foc with the fact weights, never noticed much of a difference but I'm not consistently hitting plates at 80 yds (fixed 3 pin and 55yd home range)
If you're counting grains may I suggest cutting your wrap in half.
This not only gives you twice as many wraps for your $, but shaves a few grains off the back.
I've heard back weight and front weight aren't 1:1 with FOC. For example saving 3 grains in the back is like adding 10 to front (don't know real #'s)
If you're using lighted nocks(didn't see that listed) a reflective wrap with a good flashlight can replace a lot of rear end weight.

Sent from my SM-G950U using Tapatalk
 
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I shoot a 520 grain total arrow weight with 19% FOC.

It took one shoulder shot with a 390 grain arrow with little penetration for me to make the change to a heavier, harder hitting arrow. I've been extremely happier with the results. Yes, the heavier arrow is slower but it hits harder and comes out of the bow quieter.
 
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jakelogsdon

jakelogsdon

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Sounds like a true tinkerer to me. If it ain't broke... Maybe I can make it better.
As a tinkerer myself I've played with FOC.
I've got light arrows, gt velocity, and have played with foc with the fact weights, never noticed much of a difference but I'm not consistently hitting plates at 80 yds (fixed 3 pin and 55yd home range)
If you're counting grains may I suggest cutting your wrap in half.
This not only gives you twice as many wraps for your $, but shaves a few grains off the back.
I've heard back weight and front weight aren't 1:1 with FOC. For example saving 3 grains in the back is like adding 10 to front (don't know real #'s)
If you're using lighted nocks(didn't see that listed) a reflective wrap with a good flashlight can replace a lot of rear end weight.

Sent from my SM-G950U using Tapatalk

I experimented with several brands of lighted nocks years ago, wasn't happy with arrow performance, So I ended that journey. I'm Already cutting my 7" wrap in half. I could go to a 3 fletch instead of 4. and probably cut 7 or 8 grains off the tail weight (vane weighs 6gr or so, plus a little glue). Several things have come in to play recently to get me wanting to dick with this. I want a faster arrow, for shooting long range and for hunting late season whitetails. When I started making a wishlist for this next arrow build there were a few things I wanted, that directly contradict each other dynamically. I knew I needed to come here for some insight
 
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Thanks but I can shoot out past 120 already with a 500gr arrow, I don't really feel like I need to shoot any further, I prefer to shoot my hunting arrow year-round for 3D and messing around so I can build confidence with my setup. I was commenting on distances I shoot because I was asked above by JL how far I was shooting after I said I haven't noticed any change in accuracy going from 9-16% FOC.
My apologies, I mistook you for the OP.

I experimented with several brands of lighted nocks years ago, wasn't happy with arrow performance, So I ended that journey. I'm Already cutting my 7" wrap in half. I could go to a 3 fletch instead of 4. and probably cut 7 or 8 grains off the tail weight (vane weighs 6gr or so, plus a little glue). Several things have come in to play recently to get me wanting to dick with this. I want a faster arrow, for shooting long range and for hunting late season whitetails. When I started making a wishlist for this next arrow build there were a few things I wanted, that directly contradict each other dynamically. I knew I needed to come here for some insight
I'm a tinkerer by nature as well and enjoy experimenting with the fine details of arrow building even if the practical effects may be too small to be noticeable at my shooting ability.

If you want to estimate FOC of a potential arrow build beforehand, Gold Tip has an online calculator based on component weights: https://www.goldtip.com/Resources/Calculators/FOC-Calculator.aspx

I came up with the following formula based on simple statics. It's probably not quite as accurate as the GT calculator because it treats the combined weights of all front/rear components as concentrated weights applied at the very front and very rear of the shaft. But the formula gives results within ≈1% of the GT calculator and can be put in a spreadsheet to quickly perform multiple calculations and compare potential arrow configurations:
[(front end weight) + 0.5 × (shaft gpi) × (shaft length)] ÷ (total arrow weight) – 0.5
Screenshot_20200211-113052.png
 
OP
jakelogsdon

jakelogsdon

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I'm a tinkerer by nature as well and enjoy experimenting with the fine details of arrow building even if the practical effects may be too small to be noticeable at my shooting ability.

If you want to estimate FOC of a potential arrow build beforehand, Gold Tip has an online calculator based on component weights: https://www.goldtip.com/Resources/Calculators/FOC-Calculator.aspx

I came up with the following formula based on simple statics. It's probably not quite as accurate as the GT calculator because it treats the combined weights of all front/rear components as concentrated weights applied at the very front and very rear of the shaft. But the formula gives results within ≈1% of the GT calculator and can be put in a spreadsheet to quickly perform multiple calculations and compare potential arrow configurations:
[(front end weight) + 0.5 × (shaft gpi) × (shaft length)] ÷ (total arrow weight) – 0.5
Awesome info, I wish I could go with a little shorter of an arrow. I've experimented with some slightly shorter than 29" arrows and they did not perform well at all. 29" seems to be the shortest I can go, the tip of a field point is flush with the outer edge of my riser at full draw. I've got high hopes for this Victory arrow build this spring.
 
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In my experience distance and whitetail don't go together. I have shot them at distance but they are a jumpy animal. Need to make a quiet arrow rather than a faster one. In my experience.

Tinker away. I have done plenty, and unfortunately it seems many times it's an itch you need to scratch for yourself rather than listening to someone else.
 
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jakelogsdon

jakelogsdon

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I wont shoot a whitetail over 40 yards. I'd still like to have a hard hitting hunting arrow that I can also practice with at 100 yards
 

arwhntr

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If I was shooting 3" groups at 80 yards I wouldn't be changing a thing. That said, I totally understand the want/need to tinker/experiment with different setups.

I've messed around with an FOC range of 10-22%. Found that with high FOC (19%+) my arrows would "fall-out-the-sky" dropping rather quickly at distances of 80 yards and greater. Ultimately for me, it came down to building an arrow at a specific total arrow weight I deemed "ideal" while maintaining certain aspects like micro diameter shafts, low profile 4 fletch, 4" wrap and FOC between 12-16%. Now I'm in a set it and forget it mode building the same arrow time and time again clocking in at 416g and 16% FOC.
 
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jakelogsdon

jakelogsdon

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If I was shooting 3" groups at 80 yards I wouldn't be changing a thing. That said, I totally understand the want/need to tinker/experiment with different setups.

I've messed around with an FOC range of 10-22%. Found that with high FOC (19%+) my arrows would "fall-out-the-sky" dropping rather quickly at distances of 80 yards and greater. Ultimately for me, it came down to building an arrow at a specific total arrow weight I deemed "ideal" while maintaining certain aspects like micro diameter shafts, low profile 4 fletch, 4" wrap and FOC between 12-16%. Now I'm in a set it and forget it mode building the same arrow time and time again clocking in at 416g and 16% FOC.
I'm extremely happy with the performance of this day six arrow. I've just got a few goals that I'd like to achieve and I think building another arrow is the answer. Since I'm starting from the ground up, I was contemplating a higher FOC with this build and wanted some insight from guys that had some experience messing with it.
 
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One suggestion I'll offer if you like experimenting is to use heat reversible glue (aka, "hot melt") to secure your inserts so you can easily remove them later. Pretty much every arrow manufacturer warns against using hot melt with carbon shafts, but I think that's just a CYA statement to avoid liability for someone overheating and weakening/ruining the carbon. As long as you're careful and don't apply a flame directly to the carbon (heat the end of a field point and let it conduct heat back to the insert), you won't damage the carbon. I use Bohning Cool Flex on all my arrows and haven't had any issues with inserts pulling out. If you were concerned about inserts staying in place, you could switch to epoxy once you get your arrow configuration finalized.
 
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jakelogsdon

jakelogsdon

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One suggestion I'll offer if you like experimenting is to use heat reversible glue (aka, "hot melt") to secure your inserts so you can easily remove them later. Pretty much every arrow manufacturer warns against using hot melt with carbon shafts, but I think that's just a CYA statement to avoid liability for someone overheating and weakening/ruining the carbon. As long as you're careful and don't apply a flame directly to the carbon (heat the end of a field point and let it conduct heat back to the insert), you won't damage the carbon. I use Bohning Cool Flex on all my arrows and haven't had any issues with inserts pulling out. If you were concerned about inserts staying in place, you could switch to epoxy once you get your arrow configuration finalized.
This is exactly the method I use. Start out with hot melt in the building process until you get it refined then epoxy if necessary. I learned to do this when I started paying over $15 per arrow, Hahahahahaha.
 

Beendare

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I mentioned the Easton recommendation earlier.

It should tell you something in regards to accuracy when every top compound pro is in the Easton recommended range for FOC. There might be one outlier somewhere but essentially all the pros listen to Easton. If a higher FOC gave them any advantage you can bet they would be all over it.

Now there are some stick bow guys that have had success with higher FOC...but even the top FITA recurve shooters are ALL in the Easton recommended range.

Internet advice and a couple wannabe be guys claiming otherwise...its worth noting what the professionals do. Accuracy is numero uno.

______
 
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