Brace Height and Bow Performance

[Kamu]

All just some thoughts. I shoot a Acadian Tree stick that is 50@28 I only pull 26 1/2. So here is the question. Are bows made to perform at their best at 28 inch's. Right now my brace hieght is set at 7 inch's so if I raise the brace height some will that preload the bow so I'll get a little more performance out of it.

[BWD]

You will loose power stroke by raising brace height. If your bow shoots good and is quiet where you have the brace height set now, I would suggest you leave it alone.

[atatarpm]

If you raise the brace you will get less as the power stroke will be shorter

[Kamu]

O okay thanks

[twistedlim]

According to John McCollough the difference is very minimal.  He said go with what works.  A quiet bow is better than a bow that is 1-2  fps faster.

[Moots]

I had a bowyer tell me that every bow is a little different.  He recommended starting with 6 1/2 " brace height on his bows and gradually moving the brace height out until the bow quiets.  The lower the brace height, the longer the arrow will be on the string - - a good thing.

[Stumpkiller]

Originally posted by Kamu:
So here is the question. Are bows made to perform at their best at 28 inch's.

No.  I can't recall a single instance where a bow performed better at 28" draw than at 29".    

[**DONOTDELETE**]

Originally posted by Moots:
I had a bowyer tell me that every bow is a little different.  He recommended starting with 6 1/2 " brace height on his bows and gradually moving the brace height out until the bow quiets.  The lower the brace height, the longer the arrow will be on the string - - a good thing.

Good advice here.... Every bow design has a sweet spot that the bowyer can get you real close on.... some guys have problems with arm clearance on low brace heights and raise it above the recommended height... the performance loss is minimal between 7.5" -8"   The difference between 6.5" and 8" will be noticeable at longer yardage on some bows.

[twistedlim]

Originally posted by Kirkll:
 

Originally posted by Moots:
I had a bowyer tell me that every bow is a little different.  He recommended starting with 6 1/2 " brace height on his bows and gradually moving the brace height out until the bow quiets.  The lower the brace height, the longer the arrow will be on the string - - a good thing.

Good advice here.... Every bow design has a sweet spot that the bowyer can get you real close on.... some guys have problems with arm clearance on low brace heights and raise it above the recommended height... the performance loss is minimal between 7.5" -8"   The difference between 6.5" and 8" will be noticeable at longer yardage on some bows. [/b]

Interesting, John mcCollougg said to start with the highest recommended height and work down.

[S.C. Hunter]

Well with all that said. My bows suggested brace height is 6 3/4"-7 1/4" I am at 7 1/16" finally after some settle and shooting of the bow.

If anyone has the technical info I would be interested. My resting string brace height is 7 1/16" my arrow measures 9 1/8" from string nocking point to front of riser. My arrow length is 29.5" to BOP. I draw 29.5" so I am basically only drawing the bow an additional 20 3/8" from its brace height correct. My question is if my bow is 56#@28" and I draw to 29.5" what is the actual draw weight of the bow and what performance would I see from a arrow weighing 545 grains? Sorry I should have asked the difference between that bow at the 56#@28" vs the same bow with a draw out to 29.5". Thanks

[hvyhitter]

Brace height is part of the tuning of both bow and arrow. On some bows changing your arrows may require a little fine tuning( like going from a 560gr aluminum to a 750gr maple).............

[**DONOTDELETE**]

Depending on the bows design and length of the working limb the pounds per inch is going to vary at different stages in the draw cycle. if your bow is designed to draw 30" before it stacks you are probably pulling between 61-62# at 29.5"  with a 56@28 bow.....

at that draw weight your arrows are running between 8.7 and 8.9 gpp and an average bow will put you in the mid to low 180's fps. and a high performance bow  will run mid 190's fps or higher.

 


  Interesting, John mcCollougg said to start with the highest recommended height and work down.  

I can't give you a logical reason for why anyone would recommend starting at a higher than recommended brace height and work their way down unless he was thinking of the string settling in.

seems backwards to me.    

[Sixby]

I always start at the lowest reccomended brace and work my way up When I have good stability and the bow is quiet and vibration free I stop; With my bows that is generally around 7 to 7 1/4 inches; I doubt that it matters which direction you start from. I just like to start where I have good fletch clearance and arm clearance and work from there keeping the brace as low as I can and get the results I want.

God bless you all, Steve

[twistedlim]

Originally posted by Kirkll:


 


  Interesting, John mcCollougg said to start with the highest recommended height and work down.  

I can't give you a logical reason for why anyone would recommend starting at a higher than recommended brace height and work their way down unless he was thinking of the string settling in.

seems backwards to me.      

Well Johns explanation made perfect sense to me.  Say a bow has a brace height between 8 and 7.25.  Starting at 8 you know the bow should be quiet and shoot well but maybe not the best performance.  As you work down you will hit a point where the bow is noisy and/or the the arrow flight suffers. at that point you can move it back up to the sweet spot.  I got the impression from him it is far better to have a brace height that is too high rather than too short.  Too hight= you  may loose a bit of performance, too low= noisy, erratic arrow flight, arm slap.  Hmmm seems to me John has a point to error on the high side.  
I tend to believe him since he takes the time to make some of the finest recurves and longbows made.

[Warchild]

Seems like the same theory just in reverse order. What is the difference as long as you are starting at one point (either low or high) and consistantly moving in the same direction until you hit the sweet spot.

[Over&Under]

Originally posted by Warchild:
Seems like the same theory just in reverse order. What is the difference as long as you are starting at one point (either low or high) and consistantly moving in the same direction until you hit the sweet spot.

Ding! ding! ding!...we have a winner!  

[Over&Under]

Originally posted by Kamu:
All just some thoughts. I shoot a Acadian Tree stick that is 50@28 I only pull 26 1/2. So here is the question. Are bows made to perform at their best at 28 inch's. Right now my brace hieght is set at 7 inch's so if I raise the brace height some will that preload the bow so I'll get a little more performance out of it.

Increasing brace most likely will hurt performance.

For example suppose we exaggerate it and you could raise your brace to 25"...you would only be drawing the bow 1 1/2"...your arrow may not even make it 10 yds    

But .like stated, a quiet bow is, IMO, better than speed. Besides adjusting brace up or down even an inch would only affect performance by a couple fps.

I do know some bowyers design and glue up limbs to maximize performance at YOUR draw length.

For example I had an RER XR that was marked X@26
I called Kevin and he said he specifically made those limbs to maximize performance at 26" because it was such a short draw.  If he made the limbs like he typically does, for a standard 28", they would have less performance for that customer who had a 26" draw.

I guess that's another nice feature of a custom bow and good bowyer to help get the most out of each bow for the clients draw,style, etc.

[**DONOTDELETE**]

Originally posted by Warchild:
Seems like the same theory just in reverse order. What is the difference as long as you are starting at one point (either low or high) and consistantly moving in the same direction until you hit the sweet spot.

Absolutely correct!    Six of one...half dozen of another...

  For example I had an RER XR that was marked X@26 I called Kevin and he said me specifically made those limbs to maximize performance at 26" because it was such a short draw. If he made the limbs like he typically does, for a standard 28", they would have less performance for that customer who had a 26" draw.  I guess that's another nice feature of a custom bow and food bowyer to help get the most out of each bow for the clients draw,style, etc.

This is definitely a nice feature for customers with really long, and shorter than average draw lengths.... The custom bowyer can alter the wedges and taper rates of the limb to accommodate different draw lengths for smoothness of draw and higher performance both.


  As you work down you will hit a point where the bow is noisy and/or the the arrow flight suffers. at that point you can move it back up to the sweet spot. I got the impression from him it is far better to have a brace height that is too high rather than too short. Too hight= you may loose a bit of performance, too low= noisy, erratic arrow flight, arm slap. Hmmm seems to me John has a point to error on the high side. I tend to believe him since he takes the time to make some of the finest recurves and longbows


There are definitely some really fine bowyer's out there that have differences in opinion on things. in the case of starting point of high or low brace... it really makes no difference once you find the sweet spot you are looking for.

There are many different ways to skin a cat on quieting a bow down and still not leaving too much performance on the table..... different strings and silencers can mitigate lower brace heights. But all bows are not created equally in terms of preload and hand shock attributes. some bows flat out need a higher brace because the limbs are not stopping clean.

Assuming that a low brace height causes "Erratic Arrow flight" is a poor assumption. IMO... That has more to do with arrow tuning... and arm slap is more of a wrist rotation and elbow rotation issue... i have long bows i can shoot at a 6" brace without it biting the wrist at all with good form.

[twistedlim]

Originally posted by Warchild:
Seems like the same theory just in reverse order. What is the difference as long as you are starting at one point (either low or high) and consistantly moving in the same direction until you hit the sweet spot.

Logic has no place on this forum  

[Sixby]

First , no one insinuated in any way that John McDonald is not a fine bowyer. Neither do many on here have to be told that he is as most are admirers of his work.

 Because Kirk or I or any bowyer does something a bit different than John McDonald does not mean that it has anything to do with either the quality of his work, our work or any of our abiliities.
You may believe anyone you want for any reason you want; It really makes little if any difference in this matter how you go about finding the place of brace or the sweet  spot as long as you actually have any idea at all what it is you are looking for.
Clue. stability of limb torsionaly and verticaly, queitness,. lack of vibration, fletch and arm clearance.

God bless you all, Steve