Trad Gang
Main Boards => PowWow => Topic started by: ozy clint on November 04, 2014, 02:41:00 AM
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just been preliminary tuning of an old mamba that was rebuilt for me after it lost a limb. it's now got bamboo cores. same length as original- 58". it's 55#@28" but i draw 26".
i was using an axis 500 30" long with 100gr insert and 2.5" footing. no matter what weight point i put on it was left tear. it got somewhat better with a 425gr point. is there any way these are too stiff? if so what arrow could possibly work out of a 40# bow if 500's are too stiff for a 55# bow? i'm lost again. i shot a 28" 500 and results were similar maybe worse. which tends to suggest too stiff. i'm just lost because if 600's worked then i wouldn't know of any arrow that would work out of a bow lighter than 55# but i know this isn't true.
i'm reluctant to try 400's since they ended up shooting real nice out of my 58# border with 350gr upfront.
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A bit more info is needed for an accurate assessment. How do you measure your draw length, right or left handed, are you sure you are getting a clean release, is there any contact with the shelf or side plate, are you shooting off the shelf or an elevated rest, where is your brace height and nock point set, are you using one or two nock points, do you shoot split or three under, are you paper tuning with a bare shaft or feathered arrow, how far away from the paper are you shooting, is there enough clearance from the paper to the target, what is the center shot of the bow cut to, what type and condition of string is on it, etc.?
There could be a multitude of things happening here.
With the info you have provided, my first thought is that your arrow is indeed too stiff. A 30" arrow for a 26" draw seems a little long. I would bet that the paradox of the shaft is out of sinc with the bow at that draw length, causing some contact somewhere and giving misleading results. Plus you have an internal and external footing that are compounding the stiffening acts of the footings.
If I were you, I would try a 600 shaft with the same set up. If it shows weak, you know that you've made progress. You can always stiffen them more by shortening the length, or increasing the footing lengths.
When trying something that should work and it doesn't, then try something that shouldn't work!
I have found that the axis shafts stiffen up greatly with footings.
Out of my 51#@my 28" Elkheart, I shoot 29.75" axis trad 500's with 150 grains of brass HIT insert and 125 grain broadheads with good results.
You are shooting probably 2#s less, with 2" less power stroke. I hope I helped a little. Good luck, and let us know what works for you.
Ps your nock height requirement may change when changing static or dynamic spine of your arrow.
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Pretty obvious in your avatar that you shoot right handed in which case why do you think a left tear is an indication of a stiff dynamic spine?
DDave
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Clint, if I'm not mistaken a left tear is indicating a weak arrow for you. Good Luck!!!
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the bow in my avatar is this very bow i'm tuning. so have i had a big brain fart? is a left tear weak not stiff?
i'm getting consistent results just not what i was expecting, though if a left tear means weak then it is what i was expecting.
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A left tear indicates a weak shaft for a right handed shooter. Good luck!
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A left tear is showing that the shafts are weak. No surprise there with a 500 carbon shaft. Try tuning a 400.
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Well, in my sleep deprived state last night/this morning, I see I was a little confused as well! Lol. Although it does supprise me a bit that you would be getting a weak reaction with that draw length/weight combo. Sorry if I added to your confusion. As a disclaimer, I tune all my bows with the bare shaft/planing method.
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use a 400 Bro i think you will get better results
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i think i was confusing left tear on paper with hitting left with bareshafts. thanks for the help.
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Hey Clint, download this pic onto your phone, and then you will always have the info right at your fingertips! (Don't worry about the dropaway rest part. Just read the bottom line where it says too weak, too stiff)
(http://i579.photobucket.com/albums/ss239/archeryrules/Mobile%20Uploads/2014-04/A441A69A-50A6-4B5A-B275-436C4931273D_zpsh3sqpuxn.jpg) (http://s579.photobucket.com/user/archeryrules/media/Mobile%20Uploads/2014-04/A441A69A-50A6-4B5A-B275-436C4931273D_zpsh3sqpuxn.jpg.html)
Bisch
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sweet, thanks bisch. looks like my yoke tuning is out. :biglaugh: