what brace height is faster

[Javi]

Because the bending force is at the beginning of the power stroke as the pile is forced into motion.

[**DONOTDELETE**]

You ever have one of those things you just can't wrap your head around? Well I'm definitely having comprehension backlash on this one.

let me see if I've got this right now.... as you twist the string up it's increasing the string tension preload and adds early weight to the draw.

 a shorter string also brings the string angle at full draw closer to 90 degrees, which would account for the slight weight increase at the time of release..... which in fact increases the force on the arrow at peak weight.

The speed loss is like taking your foot off the gas once the arrow leaves the string.....

Do i have this right now?

[Orion]

I think it's pretty much a wash with most bows.  Sure lowering the brace height increases the power stroke, but by how much?  Not much. For argument's sake, let's say 1/4 inch.  So we have a quarter inch more power stroke, but the draw weight is also reduced at the same time, say  1/3# (.25 inch x 2.5# per inch of draw).  On the other hand, increasing the brace height, reduces the power stroke by 1/4 inch, but increases the weight by 1/3#.  Just not enough difference in either direction to have any practical/noticeable effect on speed.

Now, if you change brace hight by an inch or more, the effect will likely become noticeable.  However, in final tuning, when we're close to the sweet spot, less than 1/4-inch in either direction is usually all it takes, usually less than 1/8 inch in either direction, and that influence on speed is negligible and almost impossible to even measure

[Bill Carlsen]

Here is what I have found. We can talk all day about how much  a brace height MIGHT affect an arrow's flight characteristics. But, each bow is different and there are "Sweet  Spots" that exist that involve the proper nocking point and brace height...even string material, that will get any particular bow shooting as efficiently as it can. When you find those spots the bow will fell better, will shoot with more stability and even quieter and you are probably adding years of longevity to its usefulness as a weapon. What I am saying is, from what I can see based on all the bows I have owned and shot, that you have to play with each bow a bit to find the parameters that make that bow shoot the best. Accuracy  and shootability depends on a couple of things....simply put good form and well tuned/matched equipment. You may make a bow faster by lowering the brace height, but at what expense?

[Sixby]

Thyere is a lot of not comparing apples to apples going on here. First to accurately compare speed you woould have to have identical bows and identical arrows and one bow braced at say 7 inches and another say at 8 inches and same weight of pull. The bow with the shorter brace will be faster unless the angle of paradox is increased causing poor arrow flight. I beleive this is the scenario that resulted in the higher brace height on the same bow being faster.

However if the bow is true centershot and you repeat this test with two bows of same poundage the lower brace height bow will indeed impart more energy to the arrow and result in a faster bow at that given poundage. When you start working with one bow and different brace heights and different poundages and possible paradox and bad arrow flight you can get completely erronious results in your test except for that one bow.

God bless you all , my story and I'm sticking to it.

Steve

[Rob DiStefano]

i'll say again ...

every stick bow will have a range of performance as dictated by design, brace height, string mass weight and elasticity, arrow mass weight and spine. there are lotsa things to tweak and compare for performance. "performance" means arrow speed, vibration, noise and stability.

the bowstring is the transmission, the arrow is the vehicle and the limbs are the fuel. lowered mass weights increase speed, and that goes for limbs, strings, and arrows. i have no clue as to what and if any amount of aerodynamics adds to the measured speed/performance of those items.

all the words in the world don't hold a candle to personal testing. do the testing and let yer personal results guide your choices of tackle.

[Rob DiStefano]

Originally posted by joekeith:
   

Originally posted by Rob DiStefano:
   

Originally posted by WildmanSC:
A too low BH can result in a very quick trip to the emergency room.  Well, not really, but if you shoot a low BH bow with poor form, it will eat your forearm and/or wrist alive....

never happen if you know how to grip the bow.  i never use an armguard, and i shoot longbows with 5-3/4" to 6-1/2" brace heights, [/b]

Well Rob I'd like to see you shoot a Brown Recluce like the one Wildman is talkin' about.  They're killers at that BH.  I ended up raising mine to over 7", closer to 7 1/2", and ended up with a nice quiet bow to shoot. [/b]

yep, some bows just demand a higher brace height.  those are the bows i don't own or shoot.    :D  

but i'll wager i can shoot any stick bow i can pull to full draw, without using an armguard and without getting string slapped.    

[Rob DiStefano]

Originally posted by njloco:
Rob, please correct me if I am wrong. From shooting a lot, I have noticed a couple of things that happen to me when I shoot the wrong way, especially with a recurve bow.

1- The higher the draw weight and lighter the arrow, the more abrupt the recoil on the bow arm, and the tighter one must hold the bow to avoid left to right movement of the bow, and better the form must be.

this one is easy - light mass weight arrows don't have the ability to absorb all the limb energy as transmitted by the bowstring.  that wasted energy goes back to the limbs and riser and yer bow hand.  stick with 9gpp arrows or higher. i rarely go under 10gpp and mostly use 11gpp and higher.  light mass weight arrows are also not good for a bow's health as they are closer to dry firing!

2- When I hit my arm guard, I am doing something wrong with my form regardless if I make a good shot or not.

whether or not you need an armguard is primarily up to yer bowhand placement.  if yer constantly string slapping the armguard, and all yer arrows are consistently hitting what yer looking at, that can't be a bad thing?  well, it is for me, personally - i don't want arm string slap at all.  it's more than that, though - for me it's about finding a secure bowhand grip that's consistently repeatable no matter whether the bow's handle is a hill dead straight or a bear recurve deep pistol.  it's just a personal thing.

[Arwin]

Will a higher brace height perform better for people who draw less than 28 inches? This is a general question since a lot depends on the bow, but I draw 27 and every bow I shoot seems better at the 7-7 1/4 inch brace.

[Rob DiStefano]

Originally posted by Arwin:
Will a higher brace height perform better for people who draw less than 28 inches? This is a general question since a lot depends on the bow, but I draw 27 and every bow I shoot seems better at the 7-7 1/4 inch brace.

this is where the talk needs to stop and the testing needs to begin.  there are SO many variables to deal with, and discover ....

[Bill Carlsen]

Arwin: I believe it has everything to do with the bow's best shooting parameters and correct arrow spine. Over the years I have seen lots of set ups that shoot lights out for the owner of the equipment shoot like dogs for another archer trying it out. Every one of us is different and each one of our bows is different and may not perform the same from person to person. i cannot fully explain it but I've seen enough of it to know it is  the way it is.

[Arwin]

 

 LOL! I think this is why I love shooting traditional gear, it's so unique to the individual!
  I did have one bow that demanded a lower(to me) brace of 6 3/4. It was a Hill Halfbreed that was tempermental if you went over or under that BH.

[Bldtrailer]

Ok the reason I started my thread is I found 2 "sweet"  spots for my stalker recurve 71/4 and 75/8 both seemed quite and both seemed forgiving & accurate. I seem to shoot the 71/4 better at my 271/2 draw with 55@28 . But my 2 Appalachian savage rivers demand 73/4 before they settle down.  

[LEWIS VADEN]

Someone please explain to me how raising the brace ht. increases the poundage of the bow.  You are still pulling the limbs to the same place, they just start out with a little more preload.

[Shawn Leonard]

Rob, I know how to grip a bow but do too my very large forearms I have a problem with string slap with bows braced less than 7.5"s. Shawn

[Rob DiStefano]

Originally posted by Shawn Leonard:
Rob, I know how to grip a bow but do too my very large forearms I have a problem with string slap with bows braced less than 7.5"s. Shawn

dude, i wish i had yer problem of large forearms and string slap!  :D

[foudarme]

Originally posted by Orion:
I think it's pretty much a wash with most bows.  Sure lowering the brace height increases the power stroke, but by how much?  Not much. For argument's sake, let's say 1/4 inch.  So we have a quarter inch more power stroke, but the draw weight is also reduced at the same time, say  1/3# (.25 inch x 2.5# per inch of draw).  On the other hand, increasing the brace height, reduces the power stroke by 1/4 inch, but increases the weight by 1/3#.  Just not enough difference in either direction to have any practical/noticeable effect on speed.

Now, if you change brace hight by an inch or more, the effect will likely become noticeable.  However, in final tuning, when we're close to the sweet spot, less than 1/4-inch in either direction is usually all it takes, usually less than 1/8 inch in either direction, and that influence on speed is negligible and almost impossible to even measure

for instance, with my 12"/62" ACS, at 12.6gpp and my shooting machine I earn 2fps when I remove 1/4" from my 7.25" brace height (test done right now with my scale & shooting machine & indoor chrono infra kit)...the draw weight decreases from 46.8# to 46.5#

[kevgsp]

lewis, imagine a really short string (or very high bh) the limbs are not drawn to the same spot...farther with a high bh

For me,  too closed a stance has more to do with string slap than grip of the bow.