FOC; highley overrated???? (and carbon vs woodies...)

[Jesse Peltan]

FrankM that is correct assuming not shooting in a vacuum.  Higher foc gives the fletchings more leverage.  This allows the arrow to straighten out faster reducing drag.  Less drag means the arrows maintain their velocity longer.  This also assumes equally tuned arrows the only thing different being foc.

[Diamond Paul]

Not positive, but I think the Olympic shooters use very high foc arrows; this is the reason for the tungsten points they use on their skinny carbon arrows.  They shoot pretty far, I think.

[Zradix]

I think they do too ( olympics ). I think they all use sights too...I think.. Having sights would take out a lot of the negative aspects of having a very arced traj.

I didn't read anywhere in this post that someone thought efoc made a less flat shooting set up.
I did say that the only way to get efoc when using the same shafts is to add mass to the tip. More mass=less speed=more arc.

Flight arrows are altogether different from target arrows.
This thread was bad enough when comparing hunting and target setups. Now we want to throw flight set ups in.
It's sorta like comparing 4x4 trucks, sportcars, and motorcycles. They all have their place and are fun, but I'm not taking a Maserati Edo Corsa across the rubicon.

The thread started as (more or less) as a question of whether efoc had a place in trad archery target shooting. I assumed (we all know about that) that he was speaking of trad archery w/o sights.

[Zradix]

Originally posted by Ragnarok Forge:
Hmm,

EFOC and UEFOC's benefits all depend on what you're trying to do and how.

Nicely said

[Rob DiStefano]

this thread is NOT about trad bowhunting, as the topic starter admits, since he can't be a bowhunter in his country of residence.  but it's worth nailing the lid on all this foc talk.  

you can think and say what you like, but some amount of positive foc DOES play a role in arrow flight and performance.  i/we new this back in the 60's but really didn't know why.  

i believe that you really want a good 13-15% foc to help get the arrow on course as it jumps outta the bow.  any more than that depends on your own testing.  and it's true that tons of game were killed with 10% foc arras.  but that's no excuse not to pursue something that one might find beneficial.

for foc to work properly, you just don't bulk up the front end without thinking about attaining a proper arrow gpp.  read that again.

here's a classic example ...  

a 50# stickbow shoots a 500 grain arrow with 125 grains at the front.  that's a nice 10gpp arrow and it shoots fast and flat.  

replace that point with one that's 200, 250 or even 300 grains and now the arrow becomes 11.5 to 13.5 gpp.  that arrow may track and hit like a freight train, but there will be a decidedly higher trajectory as the target moves out and away.

boosting the foc, for better flight tracking, means rethinking the arrow from the ground up.  that's all.  

if 10gpp is yer goal, and yer arrow is made up with a 375 grain back end and 125 grain front end, rethink the back end, make it lighter - in doing so, that alone increases foc.  more so if you also increase the front end at the same time.  a redistribution of mass arrow weight that might work out to a 300 grain back end and 200 grain front end for a total arrow weight of the same 500 grains, that now yields a dramatic increase in foc.  

foc management is easiest to work with carbons and alums, very very difficult with woodies.

as jc has said so well on this subject, and i fully concur, YMMV.

[Bjorn]

Just because you have an arrow that is EFOC does not mean it is automatically properly tuned to your set up, and the more you increase distance the more poor tuning is going to show up.
If your EFOC arrows are flying poorly at 40 yards you have a tuning problem.

[Rob DiStefano]

Originally posted by Bjorn:
Just because you have an arrow that is EFOC does not mean it is automatically properly tuned to your set up, and the more you increase distance the more poor tuning is going to show up.
If your EFOC arrows are flying poorly at 40 yards you have a tuning problem.

yes, arrow flight always comes before foc, efoc, uefoc and lmnop.  

[Richie Nell]

quote:
--------------------------------------------------------------------------------
Originally posted by Bjorn:
Just because you have an arrow that is EFOC does not mean it is automatically properly tuned to your set up, and the more you increase distance the more poor tuning is going to show up.
If your EFOC arrows are flying poorly at 40 yards you have a tuning problem.
--------------------------------------------------------------------------------

yes, arrow flight always comes before foc, efoc, uefoc and lmnop.

Yes of course...but EFOC and UEFOC are very good methods by which arrows can be tuned properly and promptly.

[Richie Nell]

Mike Walker,

"Interesting,thanks for sharing and good shooting.I'd be curious of your 3D results/scores with carbons and normal FOC,say around 12%......."

Not that you asked me but.....from my experience going from 650 gr. and 15% FOC to 830 gr. and 32-34% FOC my 3d scores have significantly improved.

However, there may be other reasons for that that I haven't learned yet but certainly would like to find out.

Didn't mean to butt in.

[Roughrider]

Flying Dutchman - Since the overall weight of your carbons is much lighter than the woodies, they leave the bow faster, but would also shed their velocity faster, which may account for the similar trajectories.  other factors such as fletching drag, shaft diameter (as it relates to both drag in flight and how the arrow leaves the bow - a slimmer arrow has it's centerline closer to the riser and rest, resulting in different flight), also affect trajectory.

Since your carbons are lighter than the woods, they would be expected to deflect easier, and also wind drift easier, and penetrate less.  EFOC will help penetration, lessen wind drift and deflection, the overall arrow weight is still less, and overcomes the gains of EFOC.  The "lever" advantage described above still works and your carbons with EFOC will require less fletching and fly better than those same arrows without EFOC.

Now, if you added 15% weight to the front of your woodies, it would slow them down, and they would lose some trajectory, but also become more stable in flight and penetrate better.

Look at it in extremes; if you try to shoot an arrow with extremely low FOC, such as with no point or insert, the arrow will often be very unstable and difficult to control - start adding point weight and the arrow gets more stable. At some point the FOC would become so high as to again be unstable - bullets are defined by their sectional density, and a very short, fat bullet preforms poorly, too.  Imagine if there were a fiber stiff enough to be an arrow shaft the size and weight of the tread, with a flat coin at the end for a tip - it would have extreme FOC, but fly very poorly.  

With two arrows of the same overall weight but differing FOC's, (within reason) the higher FOC will be a more stable and easier to shoot arrow and will maintain it's velocity and penetration better.

[Jesse Peltan]

Roughrider your mistaken about foc.  Higher foc is always better for stability as long as the arrows have the same dynamic spine.  The reason an arrow without a tip or with too much tip weight is unstable has to do with tuning not foc.  Tuning trumps foc.  Tuning really trumps everything arrow weight, foc, etc.  50% foc is optimum but impossible so we have to settle for less.  I think 40% will soon be possible for normal arrow weights.  It's not foc "within reason" it's tuning.  Higher foc is better than lower foc as long as that's the only variable changed.  If tuning changes the arrow will be unstable no matter how much or how little foc it has.

[Flying Dutchman]

Originally posted by Jason R. Wesbrock:
Flying Dutchman,

Please correct me if I'm wrong, but if I'm reading this correctly, you're light carbons with EFOC shot the same point of impact as your heavier wood arrows with normal FOC? If so, I'm not surprised, but just wanted to make sure that I understood your post.

I am not quite sure what you mean with this? To shoot the same point of impact?

[Flying Dutchman]

Originally posted by Mike Walker:
Flying Dutchman,

Interesting,thanks for sharing and good shooting.I'd be curious of your 3D results/scores with carbons and normal FOC,say around 12%.......

Ok, let's understand each other right. I dind't make these EFOCs on purpose, it was the outcome of bareshafttuning.

Now for wood: it's very difficult to change the FOC for wood. I lacquer the last 10 inches of my shaft, just for finding my arrows easier back and make it easier to follow in the flight. It's white with purple, just as my fletching is. With these shafts I use 100 grains field tips, giving me a FOC of 8,5%, which is a perfect value for 3D. After bareshafting I found out that a shaft of 5/15 40-45 at a lenght of 30,3 inches does the job.

I can look what I did on the same last two 3D tournaments I shot. I shot the last one with carbon's EFOC and the former with woodies and 8,5 FOC.

Tournament one: on 32 targets 266 points with wood (8.5 foc), and on 31 targets 338 points with carbon (20 foc).

Tournament two: on 20 targets 335 points with wood (8.5 foc) and 360 with carbon(20 foc)

The time-frame between the same tournements for number one was one year and number two was 3 months.
Keep in mind that the tournaments never are the same, they are re-build every time and always totally different. They tend to have the same level, however they become more difficult each time. Especially since we have a National Championship here..

Don't look to much to the points, since we have a totally different counting as you do, especially the second tournament.

So it is obvious I improved. Especially if you consider that the same tournaments become more difficult every time.

However what caused this improvement?

Am I learning? Yes!

Gives the higher speed of carbon me an advantage, especially for targets at 45 yards and further? Yes!

Gives the higher speed, consisticy and straightness of carbon me an advantage in shooting trough tiny holes in branches/leaves? Yes!

Gives the fact that carbons are always straight and weigh all the same give me an advantage? Yes!

Gives the EFOC me and advantage? I don't know.....

[Flying Dutchman]

And to give you guys an idea how our tournaments look like: her you see me in action and yes, it was hot! We always try to imitate real bowhunting as close as possible. The only thing is that our distances are bigger. This deer was at 25-30 yards. Just needed a single arrow(woodie,8.5% foc)to shoot it in the center-kill.

please post images no wider than 640

 http://img263.imageshack.us/img263/6428/sonjapirardbakkerv2.jpg[/IMG][/IMG]

[oddan]

Good pic Dutch. Good shooting too.

[Richie Nell]

Not that you should but...Ain't now way you're gonna get a picture on this thread any bigger than 640.

[Jason R. Wesbrock]

Originally posted by Flying Dutchman:
 

Originally posted by Jason R. Wesbrock:
Flying Dutchman,

Please correct me if I'm wrong, but if I'm reading this correctly, you're light carbons with EFOC shot the same point of impact as your heavier wood arrows with normal FOC? If so, I'm not surprised, but just wanted to make sure that I understood your post.

I am not quite sure what you mean with this? To shoot the same point of impact? [/b]

I apologize. By that I meant that they hit the same at various distances, as opposed to one hitting lower than the other.

[Jeff Strubberg]

Originally posted by Flying Dutchman:
 

Originally posted by Bjorn:
Spine trumps all for sure. What is the weight difference between your woodies and carbons?

My woodies are 12GPP and my carbons 9.4 [/b]

So you dropped 120-150 grains of arrow weight and got better penetration?


I'd say that's a huge vote for EFOC right there.

[Terry Green]

Jeff....have you already forgotten the carbon arrow history????            :D    

More a vote for carbon shafting really than some FOC number.  Remember how carbons were found to out penetraiting heavier wood arrows about 8 years ago before all the FOC stuff?????,....

Based on several factors, i.e., more dimentionable stability causing less 'noodling' at impact....faster recovery from paradox,...thinner shafting than most wood arrows...and even more dimentional stability when the shafts became radial wrap/cross weave.

Carbon arrows out penetraiting heavier wood arrows is not 'new'.

[tawmio]

Again its what you need in an arrow that counts, for hunting im very excited about the efoc, im shooting a 510 grain arrow with 225 up front, its has proved to b a great hunting setup, but for 3D i dont need it to pin a target. Accuracy is key and being confident your arrow will go where you need it to.