Brace height effect on arrow spine & tune

[RickBarbee]

Well, I have to admit - I did have some ulterior motive/was trying to prove something with this topic.

Over the years, I've seen way to many shooters go through excruciating frustrations with their bows & shooting when thinking lowering their brace height was getting them some significant extra performance, when in reality all it got them was a crappy shooting bow, and a pocket full of disappointment.

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Just recently I went through this with a buddy.

He lowered his brace height (even though he was already at the bottom end of reasonable) a full inch thinking he was going to gain some power stroke & speed.

He went from shooting pretty nice accurate groups to not being able to consistently hit the target butt at 20 yards. He called me to ask what I thought was wrong with his form to cause this to happen. He was convinced, that the extra speed he had gained was amplifying his form flaws.

I argued with him about it for two weeks before finally having to prove it to him with a chronograph.

He borrowed a chronograph, and was actually quite shocked by the results.
Not only was he losing speed at the lower brace height, but his bow was 1.5 fps faster with the brace height set higher than his original setting.

After playing with his brace heights for a couple of days, he wound up settling on one at the upper end of the manufacturers recommendation. Not only was his bow faster there than ever before, but it was vibration free, and a lot quieter. He had found that "Sweet Spot".

He would never have believed it if not for the chronograph, and would have continued to believe it was either flaws in his form, or something wrong with the bow, until his frustration convinced him to get rid of the bow, OR quit archery all together.

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I thought a discussion about brace height (what it does & don't do) might save a few from unnecessarily torturing themselves.

Rick

[DRT]

I know mine being off wore me out earlier this year. I check it regularly.

Sent from my SM-J710MN using Tapatalk

[fwood]

Nice thread Rick, thanks for posting it. You're definitely correct though in that lower is not always better or faster. Dynamic spine is difficult for some of us to wrap our heads around.

How about point weight and FOC? For a different topic; not trying to derail this one but would really like to hear your opinion and explanation.

[KenWood]

I've always wondered. What if the sweetest spot is above manufacturers upper end? I have a couple that are 8 1/2" max per manufacturers recommendation and they seem to work best at close to 9". Will that over time destroy the bow? If you think about it, your flexing the limbs farther at full draw. They are starting out with more flex. I wonder this because I already draw 30".

[Dry Bones]

I was behind, saw the thread, tried to read through. My head hurt, I looked at my bow, and said... Nah, I'll just keep shooting what I know works.
-Some people really shoot on a level that is FAR superior to the masses. To those, and I do believe Rick may be there, The small increments of Brace will affect there performance, and I can follow with the "power stroke" of the bow being optimized at a certain point just before the loss. It has a "breaking" point if you will. But I will most likely never know that exact spot as my shooting does not get to that superior level.
When my brace is way out and I have not been paying attention my groups are more erratic then normal. I then look at knock point. If it visually does not look right I check my brace to see if that may be the cause. If all checks out, then I'm shooting poorly due to me.
Rick, Thanks for the post and LOTS of information, I may be fixing to get burned at the stake here, but does that mean that ALL compound bows are then constructed and set at "peak" brace by a manufacture who automatically knows how every archer will draw/ hold the bow, and arrow they should shoot?

[RickBarbee]

Cody, a compound bow works entirely different.

Contrary to what you might think, lengthening the string, and/or shortening the cables of the compound bow increases both the draw weight, and the inline preload of the string at rest brace height. They are actually pretty easy to hotrod up.

Rick

[Dry Bones]

Sheesh, now you tell me. Since I still enjoy shooting my compound, do I need to find a specific shop to help get a little more, or should most bow shops know what to do to increase the performance a little.

[RickBarbee]

Sheesh, now you tell me. Since I still enjoy shooting my compound, do I need to find a specific shop to help get a little more, or should most bow shops know what to do to increase the performance a little.

Any pro shop should know what to do, but fair warning - it could get expensive, because it involves building custom length cables & string.

Rick

[Dry Bones]

hmm, just got my attention. "Expensive" meaning what I have has been working fine and do not need to spend any more to make anything more dead then already dead.
Rick my longbow and recurve can fluctuate at least 1/8 before I begin to notice anything, and sometimes I have found my recurve to be 1/2" shorter (due to LOTS of shooting and older B50 strings) before any attention is needed. Do you have a variance you shoot in or do you pretty much maintain one steady peek set?

[RickBarbee]

hmm, just got my attention. "Expensive" meaning what I have has been working fine and do not need to spend any more to make anything more dead then already dead.
Rick my longbow and recurve can fluctuate at least 1/8 before I begin to notice anything, and sometimes I have found my recurve to be 1/2" shorter (due to LOTS of shooting and older B50 strings) before any attention is needed. Do you have a variance you shoot in or do you pretty much maintain one steady peek set?

Even though a 1/8" change either way isn't crucial, I can see a slight difference in my left to right impact when it is off, so I maintain my brace height where I want it at all times. The first thing I do when I pick up my bow is check the brace height, and adjust if required.

Have to remember, I shoot vanes off the shelf, and tune for a slightly weaker flying arrow then most do using feather, so it's a little more critical/tricky.

Rick

[Dry Bones]

This thread surfaced on another site, and I thought it would be worth re-surfacing here as well. Really good information, and obviously rick explained a lot to me. I still feel like until we reach a certain ability we may not see some of the subtle changes, HOWEVER if we are not close to begin with the changes in brace may drastically change the feel and affect of what we have been doing. Hope 2018 is good for all and keep shooting.

[M.E.B.]

Years ago I read in a book by a well know "expert" that lowering brace height will make your arrow spine weaker and make your bow shoot faster because of a longer power stroke.

I argued that point until I was blue in the face here a few years ago, and lost.
I looked it up in several places and found that I was wrong.

I need to dig and find where I read the wrong info. My archery library is fairly large and I have not felt like looking.

[60 Deluxe]

I always tune the bow to be quiet then find an arrow setup that shoots well from that bow. I am mildly curious if and how close that tuning method comes to your testing and statistics driven method. I'll probably never know because I have no intention of buying the test equipment or over thinking this delightful stress reducing hobby. I don't want it to ever turn into something similar to golf, which seems to be stress inducing in some folks. Perhaps it would be fun if one of you fellows with a good shooting bow and time on you hands could get together with Rick and measure your bow to see if your tuning falls within the parameters of Rick's hypothesis.