draw length?

[Bear Heart]

Do bowyers measure the weight at the back of the bow or deepest part of the grip?

[VictoryHunter]

The weight at 28" is measured from the deepest part of the grip or in the case of a hill style long bow the weight would be measured at the exact center of the bow.

[Hermon]

from the AMO standards:

AMO DRAW LENGTH STANDARD
For Manufacturers
Draw length is a specified distance, or the distance at the archer’s full draw, from
the nocking point on the string to the pivot point of the bow grip (or the theoretical
vertical projection of a tangency line to the pivot point parallel to the string)
plus 1 3/4”. Draw length from pivot point shall be designed at DLPP and shall be
called TRUE DRAW LENGTH.
EXAMPLE: 26 1/4” DLPP plus 1 3/4” is the equivalent of 28” draw.
For Dealers and General Use
For practical reasons not requiring precise terms, draw length is the distance, at
the archer’s full draw, from the nocking point on the string to the back of the bow
at the arrow rest.
EXPLANATION: The standard Manufacturers is consistent with the Bow
Weight Standard as related to the pivot point. The DLPP plus 1 3/4” is compatible
to previous concepts of draw length. (See handle illustration.) Draw length
for Dealers and General Use relieves the burden of preciseness not required for
general use and facilitates determining arrow length. THIS STANDARD SUPERSEDES
THE PREVIOUS STANDARD.
AMO BOW WEIGHT STANDARD
For Conventional Bows
Bow weight is the force required to draw the nocking point of the bow string a
given distance from the pivot point of the bow grip (or the theoretical vertical
projection of a tangency line to the pivot point parallel to the string). Draw length
from pivot point shall be designated as DLPP and shall be referred to as TRUE
DRAW LENGTH.
For the purpose of uniform bow weight designation, bow weight is the force
required to draw the bow string 26 1/4” from the pivot point. This weight will be
marked on bow as being taken at 28” draw (26 1/4” plus 1 3/4” = 28”) See
DRAW LENGTH STANDARD.

[Hermon]

But who knows how each bowyer measures?  

[Kris]

Not sure about weight but brace height can be measured from either location you have mentioned.
Best to ask, obviously.  

For my own reference when tuning, I prefer the back of riser, 1/2" or so, above the horizontal rest.

Kris

[Bear Heart]

So what I am reading between the lines is that you should ask each Bowyer how they do it

[JamesKerr]

All of the bows I have ever owned have had their draw weight match up to the back of the bow.

[damascusdave]

The bottom line, if it is that important to you, is to grill the bowyer rather thoroughly in that regard...many bowyers are meticulous in their standards for bow weight...others have rather loose tolerances...I was once interested in a set of original O L Adcock limbs and when the owner weighed them, on a good scale because he posts evaluations of bows all the time, he found they were something like 5 to 10 pounds over the marked weight...and he is a friend of O L Adcock

DDave

[tenbrook]

Almost all the big name bowyers (Big Jim, Shrew, etc) measure draw weight from the back of the bow to the string.  Because most grips are 1.75" thick this usually lines up with AMO standards.  Brace height is almost always measured from the deepest part of the grip to the string.  Draw length from the back of the bow to the throat of the nock on the arrow.

Now where things seem to be all over the place to me are bow length.  AMO standards say that a bows length is determined buy actual string length + 3".  I have had 3-4 big name reflex/deflex bows side by side in a 62" length and they were all from 1-4" different in length.  I personally use the AMO standard.

Hope this helps!

Tenbrook

[Bear Heart]

DLPP seems like the only way  to make it standard.

[**DONOTDELETE**]

all bowyers that follow AMO standards measure from the back of the riser, and keep the riser depth at about 1 3/4" in depth. the exception to the rule would be ELB grips that are wider and go down to 1.5" in depth.  Kirk
 

[Hermon]

Just out of curiosity I measured 8 of my bows for the distance from the deepest part of the grip to the back of the bow (at the height of the shelf). They ranged from 1 1/2" to 2".  

So if each bows measured draw weight was the same at 26 1/4" DLPP and we were to measure draw weight of each one to the back of the bow there would be a 1/2" difference in draw length.  Assuming a 3# per inch of draw for arguments sake, we would read 1 1/2# diffence in draw weight. Or +/- 3/4# from the thicker riser to the thinner riser from the AMO standard.  Basically, however a bowyer measures it (either 26 1/4" DLPP or 28" to back of the riser) it really insn't a significant difference.  Heck, two diffent scales could show that much difference.  jmo

[Sixby]

The bows I build are 1 3/4 from the deepest point of the grip to the finished front of the bow. Exception is like Kirk said , longbows with 1 1/2 in for a more circular conformation.

God bless, Steve