Importance of FOC ??

SnapT

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I'm planning on purchasing some more arrows and wondering about adding some weight to the front to increase FOC and whether its worth it or not, and how it will effect arrow flight .

I'm shooting a hoyt carbon defiant 34 @ 70 lbs with a 30.5 draw . Arrows are currently black eagle spartan , 250 spine and they are weighing in at 468 with 285 fps according to archery calc . This is with a 100 gr field point (and will likely be shooting a 100 grain broadhead )
Is adding the black eagle screw in insert weights going to really do much (thinking the 30 grain version) or am i just over thinking this and making it too complicated then it has to be lol ??

cheers

ps obviously I am green as grass .
 

Ashy Larry

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It will give better arrow flight and better penetration. Also be a touch quieter. Take advantage of that draw length and shoot a spear at them.
 

Btaylor

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Don't know that weight system and if you could go 15 grains. If so, you could switch to 2.5 feathers and get nearly the same gain in foc with almost no change in total weight or speed.
 

Elc1973

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Why not try a 125 grain field point to see if it does you any good? That will get you close to the 30 grain insert your thinking about.
 
OP
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SnapT

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Thanks guys .
In no particular order .

I'm too old to look cool on or off the internet .
Do not know what OT2 is .
thought about going to 125 gr field points but have many 100 gr broadheads (could give to my brother though and get 125)

cheers everyone
 

N2TRKYS

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There's no way I would add additional weight to the end of my arrow. I would buy a overall heavier arrow, if I wanted more weight.
 

Read1t48

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Im also a bit surprised you're not noticing a bigger difference at 60yds. I sling 100gr with great confidence. I'd say use what you're most accurate with and you'll be fine.
 

Where's Bruce?

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Tony Trietch

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First off, yes. A higher FOC will give you better flight and penetration.
You and I shoot almost the exact set up, I have a 29" draw and the Defiant Turbo so with your 30.5 draw in the regular Defiant our bows are spitting the arrows out in a similar speed and those 250 spine arrows are going to allow you room to add weight up front.

The OT2 program is great for running the numbers before you actually build the arrows. It will show you your foc and needed spine when used with your exact bow set up. This is a very detailed program that will allow you to dial in your arrows along with print off sight tapes that are perfectly matched up to your bow. I highly recommend OT2.

I have not used the Black Eagle screw in weights but think that is exactly the route I would take if I were you. Get OT2 trial version, run numbers that keep your arrow spined well and still increase FOC, screw in the weights you plugged into OT2, shoot and confirm.
 

5MilesBack

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It depends. What's your FOC right now? Personally I haven't seen much difference in accuracy between arrows with 9-16% FOC. As for penetration.......it's hard to tell what the difference would be with a small FOC gain. But a 468gr arrow doing 285fps shouldn't have any issues with penetration on anything in NA with a decent BH.
 

Beendare

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It will give better arrow flight and better penetration. Also be a touch quieter. Take advantage of that draw length and shoot a spear at them.

^^Yep. FOC is the most over exaggerated criteria in archery. I've found some FOC to be good but achieving very high FOC is a folly.

The Easton recommended range is 6%-16% [from memory]...you would be wise to stay close to that.
 

225nontypical

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I am shooting a carbon defiant turbo 70#, 29.5" draw. I was shooting axis 300 shaft with 125 grain heads, but it was right on the edge of to weak of a spine. it would shoot field points fine but with broadheads it would shoot left unless I dropped down to a 100 grain head then it was perfect. I also had to run it nock high on the bow and it would shoot nock low through paper unless I ran it higher than I felt was acceptable. but those arrows with the 125 grain heads weighted 495 and shot at 293 (average). my FOC was 10%
I am now shooting a blackeagle X impact 250 spine arrow. I am running 195 grains up front it weighs in at 485 and I am averaging 299 FPS at 16% foc.
the blackeagles are out penetrating the Axis arrows by a couple inches and seem to hit the target much harder. I think this a combination of reasons, small diameter, fast and more FOC. I do believe FOC is important but I do not think you need to be in the extreme range. Just from my experience I will now be trying to build my future setups right around 15% FOC while keeping the weight close to 500 grains and my speeds at 285+ I think this setup will give the best of everything.
 

Beendare

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I am shooting a carbon defiant turbo 70#, 29.5" draw. I was shooting axis 300 shaft with 125 grain heads, but it was right on the edge of to weak of a spine. it would shoot field points fine but with broadheads it would shoot left unless I dropped down to a 100 grain head then it was perfect. I also had to run it nock high on the bow and it would shoot nock low through paper unless I ran it higher than I felt was acceptable. but those arrows with the 125 grain heads weighted 495 and shot at 293 (average). my FOC was 10%
I am now shooting a blackeagle X impact 250 spine arrow. I am running 195 grains up front it weighs in at 485 and I am averaging 299 FPS at 16% foc.
the blackeagles are out penetrating the Axis arrows by a couple inches and seem to hit the target much harder. I think this a combination of reasons, small diameter, fast and more FOC. I do believe FOC is important but I do not think you need to be in the extreme range. Just from my experience I will now be trying to build my future setups right around 15% FOC while keeping the weight close to 500 grains and my speeds at 285+ I think this setup will give the best of everything.

You seem to be insinuating that FOC is the reason for your better performance....what about the fact you were Underspined to the point of showing weak in a target???? This is one of the worst things a guy can do as it makes it almost impossible to tune and your accuracy is unpredictable due to rubbery arrow right out of the bow.

Spine is more important than FOC....and underspined condition is the reason I think many guys have a problem tuning their bows.
 

225nontypical

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You seem to be insinuating that FOC is the reason for your better performance....what about the fact you were Underspined to the point of showing weak in a target???? This is one of the worst things a guy can do as it makes it almost impossible to tune and your accuracy is unpredictable due to rubbery arrow right out of the bow.

Spine is more important than FOC....and underspined condition is the reason I think many guys have a problem tuning their bows.

I said I think its a combination of things that are giving me better penetration, and I believe FOC is one of them, along with micro diameter shafts and the little extra speed I am getting. now there is no doubt that with the stiffer shaft the transfer of energy is greater IMHOP.
now the interesting thing with my axis arrows is we could tune it running nock high and get perfect holes in paper at 5', 10 yards and 20 yards bare shafts to tune and shoot with the fletched arrows. I was not until we put broadheads on that we saw the arrows start to shoot left some. It was not a lot though but enough to prove to me that the axis 300 was weak. like mentioned when I went to 100 grain heads the arrows would go back to center. I want to make sure I am clear though with field points they all shot in the same spot, the broadheads are what brought out the final signs of being weak. that's when I got some 250 spine arrows and was able to move my rest back to perfectly level and run more weight up front mostly just to get my total arrow weight up where I wanted it.
FYI if you look at almost every spine chart out there the 300 spine should be fine in my bow, and it not.
 

TXCO

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When shooting long distance or in high wind, Ive always seen better accuracy on a higher FOC arrow all else being equal. If you were just wanting to test it, I would get some 125 heads and go shoot them side by side to your 100s at 70 yards to get a feel for difference in performance. If you dont plan to shoot past ~30 then it shouldnt make a difference.


Sent from my iPhone using Tapatalk
 

Beendare

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Oh and i agree proper spine is more important then FOC!

^^^Gotcha...good clarification. I totally agree.

Many of the problems I've seen over the years with friends not being able to tune their bows was due to them being underspined. In a modern compound, a guy wants to avoid being underspined......or even close.

I've never seen a conclusive study where very high FOC was a scientifically proven advantage.

I've never come across a legitimate pro that uses very high FOC as their primary criteria in arrow selection- not one.

I have seen heavy arrows far outperform light arrows on penetration.
 
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