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Avalanche123
07-25-2008, 06:15 PM
This is from a website I found. I am curious what you guys think of this? I checked my arrows on my recurve and my point of contact is well ahead of my grip yet my arrows shoot fine.

However I am having trouble tuning my heavier grizzly sticks. Anyway, what do you think?

Your arrow rest? Extremely important for good arrow flight. Shoot off the shelf or use an elevated rest. Really it's personal choice but as a rule, instinctive shooters like to have the arrow as close to the hand as possible, that means shooting off the shelf. Many gap/point of aim shooters prefer an elevated rest. Either way, the point your arrow contacts the bow should be directly above the pressure point/low point in the grip. Many arrow shelves are not designed to do this so you need to build up the shelf with layers of leather, the rug side of Velcro, or something to get the contact point in the correct place. See the figure below:
http://www.alaskabowhunting.com/images/site/tuning_bio_clip_image005.jpg
If the contact point is in front of or behind the low point in the grip, it makes the bow less forgiving to torque. It creates an underdraw or overdraw condition. They can be shot well that way with good form but they can be shot better if the contact point is in the proper place. The shelf material should provide some cushioning. The rug side of Velcro works well as does seal skin, or spongy leather. Your side plate in the sight window should be as thin as possible getting your arrow as close to center as possible.

Tuffcity
07-25-2008, 09:58 PM
I think if you shoot a bow with a radiused shelf that it doesn't make much difference. I was having trouble getting what I considered good flight with heavier arrows and tried a small contact point as indicated in your diagram- made minimal difference. Switched back to a piece of seal skin on the shelf and the side plate and upped the FOC to ~20% and it made a big difference (for the better).

Your mileage may vary... :)

RC

Avalanche123
07-25-2008, 10:15 PM
Tuffcity, I found this on the "net";

Common F.O.C.s for each style of archery.
FITA 11-16%
3-D Archery 6-12%
Field Archery 10-15%
Hunting 10-15%
Use the following formula to calculate the F.O.C. of an arrow.
L= Correct Arrow Length – Distance from bottom of nock groove to end of shaft.
A = Distance form the bottom of nock groove to finished arrow balance position (includes weight of point plus insert, nock system and fletching)

http://www.socalarchery.com/Information/foc.jpg
AMO-Standard F.O.C. balance formula
F.O.C.%= 100x(A-(A-L/2)
------------------
L

How did you increase your FOC? Did you add weight to the tip? My tip weight is pretty heavy as is (315+) for my heavy arrows which are the ones I am experiencing problems with. They actually shoot ok but appear to "kick out" mid-flight before straightening out. And that "kick out" annoys me.

I am experimenting with different options right now.

Tuffcity
07-30-2008, 05:42 PM
AV,

What has your FOC calculated out as? What are your arrows spined at?

I went weight at tip with an ~100 gr insert that I made with aquarium air tubing and #5 shot. I was just playing around to see what would happen. Good things as it turns out. :) You might have to reduce your BH weight.

Rc

greybark
07-30-2008, 08:24 PM
:wink: Hey A123 , The kickout you mention is caused by one or combination of three things -- One , improper spine , Two Riser centercut to far and not allowing the arrow to bend for archerer` paradox and Three not enough brace height .
Cheers

Bigbear
07-31-2008, 11:03 AM
I think Spine is Prob the Most thing that is over looked. Even if a Person shoots a 50 pound recurve, and Figures oh 50-55 shafts are good. As you start to add Tips, Cut to length, the spine dramatically changes.

A 50-55 spine shaft Cut down to 28-29 could end up a 55-60 shaft.

For me I take a few different spine shafts EG: My bow Is a Chek-mate Take down Hunter II 49@27' I bare shaft spine, what ever weight tip I want to shoot, and Nock. Then I start with a full Length shaft. I started with 50-55's with 125gr, 100 gr, and trim 1/4 in at a time. to get the Best arrow fight. But with this spine of shaft I couldn't seem to get good arrow flight , No mater what i did .
The best that work for Me was 11/32's 40-45 cut to 28 1/4 100 Gr tip. These worked out to about 51 spine. With No Fletch they flu like darts right out to 20 yards. The finish and cresting and 5 1/2 Shield cut feathers the came to just over 500 Gr.
This works for me, so Its Just a suggestion.There is lots of Different opinions out there, There not necessarily right or wrong , but they work for whom ever
Have Fun Traditional Is a Blast.

Avalanche123
07-31-2008, 08:47 PM
I haven't had time to address some of the questions posed as I've been preoccupied. I will calculate FOC and look into this abit closer in the next few days.
Thanks!