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Target Tony
June 12th, 2005, 09:56 AM
is there any leeway for this in the rules ?

at our home shop i set my bow at 63 lbs and weighed my arrows on a digital scale at 315 grs..

so when i went to St Joseph to shoot the IBO i was wondering what if they weighed my arrows and they came in at say 310 grs.. maybe there scale is off from mine...

and what if there draw weight scale is off also say 1 lb heavier.. that would mean my arrows would weigh 310 at 64 lbs.. which sure isnt 5 grs per pound....would this get me DQed for having equipment not being 5 grs per pound ?

since then i have lowerd my poundage to 61 1/2 lbs and arrows that weigh 313grs... i recalibrated my scale with a known weight and found that my arrows now weigh 313 grs... so im within the rules like before just not as close to the edge...

Shoot Strong
Tony

mnhoyt3d
June 12th, 2005, 10:29 AM
I shoot the same bow ,same DL,at 63lbs.
When i build an arrow , I figure 64lbs and 5.1gpi=326gr

There is to much stress ,to worry about not passing tech.

plus I can still hit 300fps :thumbs_up

JAVI
June 12th, 2005, 10:33 AM
I would suggest you not set a bow up to the bleeding edge of the rules…

Tip….. If you set your bow at 280fps indoors and then go shoot outside on a 95 degree day it will shoot a few feet faster…

HoytShooter88
June 12th, 2005, 10:55 AM
I think there is some leeway Tony..

DDD in Idaho
June 12th, 2005, 11:22 AM
I would suggest you not set a bow up to the bleeding edge of the rules…

Tip….. If you set your bow at 280fps indoors and then go shoot outside on a 95 degree day it will shoot a few feet faster…


Not if you are using a good quality string that doesn't stretch in the heat. :wink:

DDD

JAVI
June 12th, 2005, 11:23 AM
Not if you are using a good quality string that doesn't stretch in the heat. :wink:

DDD

Bull.... :wink:

DDD in Idaho
June 12th, 2005, 11:48 AM
Javi,

It seems to me that you have become (or are TRYING to become) some sort of a legend in your own mind!!

It would appear that your opinion is the only one that counts and that you are the resident expert on all topics concerning archery as it exists today.

Believe it or not there are some of us that have been in the game long enough to KNOW about that about which we speak. We too have a right to speak on topics without being subject to your inane ramblings and (sometimes) moronic statements.

PLEASE explain to me - in some sort of realistic terms - not "Javi-isms", why the hell it would make a difference in the speed of a bow whether or not you were indoors or outdoors in the heat.

Since hotter air is thinner (ask any pilot) I guess that there could be some VERY SMALL variation because of string speed, but other than that I would suggest that there is a distinct possibility that you are as full of feces as a 40 pound robin!!

As an example (only one, but I have more), three or four years agoI checked the speed of my bow here at home, Idaho, indoors and in an airconditioned range - it measured 283 fps. I traveled to the Cabela's ASA tournament in Nebraska, the temp. outside was over 100 the first day and 105 the second (they even cancelled some kid's shoots). I shot well enough to get chronographed both days and my bow speed (with GOOD quality WC strings) didn't change even one foot per second!!!

At the same time there were MANY folks that had been playing at the outer limits of the speed game that were getting DQ'd because their strings were stretching and poundage was going up. They WERE NOT shooting good strings.

In short, there is more than one side to the story!!!

DDD

Target Tony
June 12th, 2005, 11:53 AM
Yes Javi i have heard that heat will not only effect your string but your limbs and riser..
thats why i try to set my bow in the shade if at all possible to avoid direct sunlight .. and keep it out of a bow case in the trunk or inside a vehicle on a hot day...

but this could fall onto anyone.. what if there scale was off 10 grains and the bow poundage was off 3 lbs heavier. it would catch a bunch of people..

this is where the IBO should just adopt the 280 rule like NFAA or ASA and be done with it..

Shoot Strong
Tony

JAVI
June 12th, 2005, 11:58 AM
So sorry but all string material will stretch in the heat... the only difference is how much.... get a chronograph and try it... the difference may only be a couple of feet per second but if you set your bow up in doors at 68-70 degrees and shoot awhile outside in 95 degree heat the bow will be faster by a couple of FPS... So if you set the bow at say 285 for ASA then you could well be over when chronographed especially given the variances in chronographs...

If knowing this makes me an expert then I guess I am one...

Target Tony
June 12th, 2005, 12:00 PM
heres what i found ont he IBO website.. i dont know how i missed this...


" 15. EQUIPMENT

A. 5 grains per pound or 280 FPS (shooters choice)

Shooter's arrows must weigh at least five grains per pound of shooting weight. Shooting weight is defined as the peak draw weight (maximum draw weight or thrust weight, which ever is greater) that is obtained within the maximum draw cycle. Shooters will be allowed 5 grains for scale differences. Shooters at the maximum end of a weight allowed for a class will be allowed two pounds for scale variation, but arrow weight must follow bow weight. Equipment will be checked at random.

The five grains per pound limit will not apply if the shooters bow and arrow combination generates less than 280 FPS of arrow speed. If the arrow speed is higher than 280 FPS the shooters equipment will be subject to the 5 grains per pound limitation. Shooters will be allowed a 3% grace for chronograph differential. When a shooter is asked to have his or her equipment checked they will be required to choose which way they would like it checked. One way or the other, not both.

Please note: It is the shooter's responsibility to maintain their equipment within this rule. "

this pretty much sums it up.. they allow 5 grs variance for arrow weight but nothing on bow poundage unless your at the max end.. so those of us that run our equipment close better check it before we go out on the IBO courses...

Shoot Strong
Tony

Doc
June 12th, 2005, 12:07 PM
is there any leeway for this in the rules ?

at our home shop i set my bow at 63 lbs... weighed my arrows and they came in at say 310 grs.

Without going into cautions about skating the edge or 5 grains per pound or being under it because of warranty/safety issues, if somebody does ask to weigh your arrow and draw weight, I don't think 5 total grains is going to make any difference, there has to be some leeway for scale variations and % error of the measuring devices. However just to be absolutely sure, put a heavy coating of arrow lube on your arrow before they weight it. A grain isn't much weight at all. 1 ounce=437.43 grains

JAVI
June 12th, 2005, 12:21 PM
Javi,

It seems to me that you have become (or are TRYING to become) some sort of a legend in your own mind!!

It would appear that your opinion is the only one that counts and that you are the resident expert on all topics concerning archery as it exists today.

Believe it or not there are some of us that have been in the game long enough to KNOW about that about which we speak. We too have a right to speak on topics without being subject to your inane ramblings and (sometimes) moronic statements.

PLEASE explain to me - in some sort of realistic terms - not "Javi-isms", why the hell it would make a difference in the speed of a bow whether or not you were indoors or outdoors in the heat.

Since hotter air is thinner (ask any pilot) I guess that there could be some VERY SMALL variation because of string speed, but other than that I would suggest that there is a distinct possibility that you are as full of feces as a 40 pound robin!!

As an example (only one, but I have more), three or four years agoI checked the speed of my bow here at home, Idaho, indoors and in an airconditioned range - it measured 283 fps. I traveled to the Cabela's ASA tournament in Nebraska, the temp. outside was over 100 the first day and 105 the second (they even cancelled some kid's shoots). I shot well enough to get chronographed both days and my bow speed (with GOOD quality WC strings) didn't change even one foot per second!!!

At the same time there were MANY folks that had been playing at the outer limits of the speed game that were getting DQ'd because their strings were stretching and poundage was going up. They WERE NOT shooting good strings.

In short, there is more than one side to the story!!!

DDD
Last time I checked almost all material is affected in some way by variances in temperature. You’re saying that something about a good quality string such as those made by Winner’s Choice somehow cancels out those variances; is this really possible? What about a string made of the same material by someone else? Or is it only Winner’s Choice that has discovered the secret? What about the changes in elastic properties of the springs (limbs) or the riser due to the differential? Are all of these things canceled out by the miracle string?


Oh... if you have a problem with me or my advice... just come out and say so... don't beat around the bush... :beer:

xpuncher
June 12th, 2005, 12:32 PM
There is leeway on speed but, not on 5 grains per pound rule. You can check your equipment before the shoot with there scales.
If IBO would just adopt the 280 fps rule and be done with it life would be easier. :eek:
It would also level the playing field for guys who have shorter draws compared to guys that pull 29" plus and have bow speeds well over 300fps. :eek:
Heaven forbid IBO do the simple thing!
Put a 280 fps rule in effect and I bet there will be quite a few guys getting extremely upset. This means they have to learn how to judge yardage better and, not rely their bow speed to compensate for miss jugded yardage. :angry:

johnhames
June 12th, 2005, 12:49 PM
Last time I checked almost all material is affected in some way by variances in temperature. You’re saying that something about a good quality string such as those made by Winner’s Choice somehow cancels out those variances; is this really possible? What about a string made of the same material by someone else? Or is it only Winner’s Choice that has discovered the secret? What about the changes in elastic properties of the springs (limbs) or the riser due to the differential? Are all of these things canceled out by the miracle string?


Oh... if you have a problem with me or my advice... just come out and say so... don't beat around the bush... :beer:

Javi,
If the string stretches, longer draw, more poundage. But the cables also stretch, more relaxed limb, less preload, lighter poundage. Won't these cancel each other out? Or is the string mechanically the controlling dynamic? John Ames

JAVI
June 12th, 2005, 02:07 PM
Javi,
If the string stretches, longer draw, more poundage. But the cables also stretch, more relaxed limb, less preload, lighter poundage. Won't these cancel each other out? Or is the string mechanically the controlling dynamic? John Ames

I think it would be a combination of factors. But if you keep the discussion confined to the string/cables; I believe in most cases the string is quite a bit longer than the cable or cables which would by ratio make the string more of a controlling entity.

Now on the hybrid cam bows since the control (slave) cable is effectively a detached part of the bow string any elongation of it will exacerbate the effect of stretch in the string.

Jose Boudreaux
June 12th, 2005, 02:13 PM
This thread is definitely worth watching

DDD and Javi are both engineers...I better get out the dictionary :D

DDD in Idaho
June 12th, 2005, 06:51 PM
Javi,

I would suggest that, if you are shooting a bow that has a riser with "elastic" properties, all bets are off. Worry a LOT about it being out in the sun. :)

Back in the days of sand cast risers and older formula polymers and resins, maybe there was a reason to worry, and I still keep my bow out of the sun when I'm not shooting - much to anal I think. :cool:

I can also remember the days when white limbs, with the associated chemical makeup of that particular gel coat layup were worse than any other color.

But -- in this day and age with the improvements that we have with forged, machined or extruded (or a combination thereof) risers, modern polymers and the advances that have been made with arrow technology, the heat is almost not even something to worry about. Sure, all materials are affected in one way or another by heat, but simply not that much. Even if you allow for "stacked" affects.

If a string is made out of poor materials, or made poorly, it will stretch, it is the most stressed component of the system - other than the limbs which (I would think) run a close second.

Back about 10 years there were several of us that just HAD to know about how temperature affected the bow and arrow set. We froze them and baked them, we twisted and loaded them, and we did other things that I wonder to this day WHY we were so inclined.

The conclusions that we came to were varied, one bow would be affected and one wouldn't. We could come to no other conclusion than it was a particular riser. We did find that some of the early, all carbon arrows were DRASTICALLY affected by temperature. Made you not want to shoot at a deer in sub-zero weather.

Anyway, even back then we found a dramatic difference in string quality. Material used and the number of strands seemed to be the big difference.

No, I didn't say the WC was the ONLY one to make a good string. I DID say that the effects of temperature are largely negated by using a good quality string.

DDD

JAVI
June 12th, 2005, 07:14 PM
I agree that the string material of today is of much better quality than those we had in the past, but they still stretch that is something that I doubt will ever be completely eradicated. Many of the string companies are now preloading the material to lessen the creep and even steaming the strings to hurry the break-in period, they are walking a tight rope in my opinion…

As to the elastic properties of 6061-T6 aluminum I do believe it has a certain flex limit before it permanently distorts and as with other metals it will be affected by temperature. As you said the amount is the question.

I just don’t want folks to believe that because they have a “GOOD” string they can push the rules limits with impunity. And I’m pretty sure you will agree with that…

FoggDogg
June 12th, 2005, 09:32 PM
Javi doesn't need anyone to stick up for him, but here's my 2 cents. He's done more for this board than everyone combined w/ the exception of the Martin family.

In his first reply, he only stated that heat would change the speed of your setup. Not how much, but that it would. DDD then argued that point, and then turned right around and stated if it did, it would be a couple fps. Talk about a fast cave in! :eek: Second, has anyone thought that the extreme heat at the Cabelas shoot might have been offset by the thinner air at DDD's home elevation? Just food for thought.

DDD in Idaho
June 18th, 2005, 12:28 PM
Javi doesn't need anyone to stick up for him, but here's my 2 cents. He's done more for this board than everyone combined w/ the exception of the Martin family.

In his first reply, he only stated that heat would change the speed of your setup. Not how much, but that it would. DDD then argued that point, and then turned right around and stated if it did, it would be a couple fps. Talk about a fast cave in! :eek: Second, has anyone thought that the extreme heat at the Cabelas shoot might have been offset by the thinner air at DDD's home elevation? Just food for thought.

Foggy,

Here are a couple of quotes from this thread;

This one is from me:

"As an example (only one, but I have more), three or four years agoI checked the speed of my bow here at home, Idaho, indoors and in an airconditioned range - it measured 283 fps. I traveled to the Cabela's ASA tournament in Nebraska, the temp. outside was over 100 the first day and 105 the second (they even cancelled some kid's shoots). I shot well enough to get chronographed both days and my bow speed (with GOOD quality WC strings) didn't change even one foot per second!!!"

Then there is this one ----- FROM JAVI!!!!!!

"the difference may only be a couple of feet per second but if you set your bow up in doors at 68-70 degrees and shoot awhile outside in 95 degree heat the bow will be faster by a couple of FPS..."

Perhaps you could show me where I did this "fast cave in"????


Second:

" has anyone thought that the extreme heat at the Cabelas shoot might have been offset by the thinner air at DDD's home elevation? Just food for thought"

Food for thought -- yes.

But, if you spend a minute doing just that - thinking - you would realize that the factors of (admittedly) thinner air in Idaho and the higher temperatures in Nebraska causing a string to stretch (a poor quality one :D ) would be ADDITIVE, they would NOT offset each other.

Try again, but I really DO think that Javi can do better on his own than he can with you "helping" him.

DDD