Simple spine question pertaining to a long draw

[UCBerzerkeley]

To keep it short -- I have a fairly long draw (31.5sh), and get confused reading spine charts bc I need to extrapolate so often. Arrows seem to fly fine (no expert). Anyways -

Bow: 40@28 (31.5 draw)
Arrow: 2117 (33") (~400gr)
Points: 200g up front (25gr insert, 175gr head)
T.A.W. ~ 600gr

Step down to 2020? 2018? Would it matter? Maybe something to consider - I certainly plan to move up the poundage chart, but am stuck with the current bow for now.

Cheers

[moebow]

According to Stu Miller's dynamic spine calculater, you should be ok with 2117s by reducing your point weight to about 150.  This presumes a center shot bow and fast flight string.  Are you sure that you have that long a draw??  Just wondering, I'm 6'3" with long arms and draw 29.5.

If you have "Excel" or "Open Office" get Miller's spine calcualtor and you can run "what-ifs" to your heart's content.  It will definately get you in the ballpark with NO extrapolation needed.

[BobW]

yep, get yourself a copy of Stu's spreadsheet.  At my 32+" of draw, the charts were not very user friendly.

[Oregon Okie]

yup.. get the calculator from Stu.

[UCBerzerkeley]

Moe, I'll check my draw again today, but I hit that pretty consistently. I'm 6'4'' also with long arms.

cheers to all you tall fellas

[UCBerzerkeley]

That calculator is awesome. Never seen anything like it. Seems I am fine with the 2117, and can fool with the weight up front. I admit I like it heavy there, keep up that FOC

For anyone that may have been looking - look no further

 http://heilakka.com/stumiller/Dynamic%20Calculator%20Instructions%20Rev%208-9-09.pdf

[Dave Bulla]

UCBerzerkeley,

Your link didn't have the drop down pages mentioned so I googled "Stu Miller spine" and found his website.  Looks like all the info is there.

But....I can't download it.  Get a pop up block saying something about "windows can not download this file because it does not know what program created it" or something like that.  What do I have to do to download?  I don't know much about that stuff and I'm always afraid to click on stuff without knowing it's right.

[dragon rider]

Dave,

It's a .pdf file.  Download, if you don't already have it, a free copy of the latest version of Adobe Reader - I think it's version 9 - and then you should have no trouble at all.

[Dave Bulla]

I've got adobe reader 7.0 (so I guess I'll have to update?) but I'm using Firefox for my web browser and when I get the box to choose either open or download, and hit the browse to choose what program to use adobe is not there.  It's in my programs list but not in the box that pops up if that makes sense????

[Richie Nell]

I have plugged in my bow setup information in that spine calculator numerous times.  I would make certain everything was just right and every single time the recommended spine was not even close to what I really needed.  Not even close.

As a matter of fact...I will try it again rat now.

[Richie Nell]

And again, not close...46.8 and 83.3 are the two numbers that should be about equal.

Oh well my arrow shoots great anyway.

[Night Wing]

It works for me beautifully.

[BobW]

set me up well

[BobW]

Dave:

Stu's calculator will not run by itself, it is a worksheet that runs inside a spreadsheet program.
You need either Excel or Open Office (Calc) to run the program.  Open Office is free from Sun Micro Systems, but a large download.  The .PDF file is the instructions that can be opened with Adobe.  Save the file (to desktop or in your "my documents"), then either double click it to run it (assuming you have a spreadsheet program), or start the spreadsheet program, and then use "file" - "open" and pick the file you downloaded to open.

BobW