Drawlength and powerstroke

[Ryan Rothhaar]

These threads are interesting.  I especially enjoy technical input from bowyers as well as "experienced" (ie older) guys.  I wish there was some way to quantify the effect.

I do know that when I went from 28 inch draw to 29 1/2 after my eye surgery that allowed me to stretch out without hitting glasses I was impressed with both the power increase and accuracy increase.  The new eyes may have had something to do with the accuracy, but the power was for sure powerstroke.

R

[grizz]

Ryan, if the bow was the same, you just added one and one half inches of draw,increased the bow weight by maybe five pounds, maybe hit the arrow spine more correctly, and shot tighter groups! Just my 5 cents worth.

[awbowman]

I draw 26 1/2".  I used to shoot a 58# BW recurve, and it didn't seem to me that I was keeping up with the guys drawing 28" at even 50#s with properly preloaded limbs.  
Powerstroke is a BIG advantage, just as it is with a wheelie bow.  Can't fool physics guys.

[Earl E. Nov...mber]

Typically the weight of draw per inch, 2 1/2# is the accepted norm.
A far as power is concerned, the area under the curve should be a good comparison of one bow to the next.

A better comparison would be to measure the weight at a given length as you let down. This allows for the hysteresis (Loss due to internal friction) of the bow

[Zbone]

Now, I have a headache...8^) This stuff ain’t suppose to be rocket science…8^)

Gotta agree with ya Javi...
Been doing this stuff a long time and this is the first I ever heard the term "preload".

Can someone please enlighten me?

Thanx

[Sixby]

Preload is the poundage at correct brace for the bow design. It varies greatly with design. Say from a string follow bow to a highly reflex deflex design. the string follow bow generally would have much less preload. It would also be a less effiecient bow. However a lot of guys love the way they shoot so they will sacrifice the speed and effiecieny for the special feel of a string follow bow. And VS versa

God bless you, Steve

[Margly]

Originally posted by Sixby:
Preload is the poundage at correct brace for the bow design. It varies greatly with design. Say from a string follow bow to a highly reflex deflex design. the string follow bow generally would have much less preload. It would also be a less effiecient bow. However a lot of guys love the way they shoot so they will sacrifice the speed and effiecieny for the special feel of a string follow bow. And VS versa

God bless you, Steve

Very good explaination  

[Zbone]

Thanx for the explaination.

[cahaba]

Originally posted by Bill Carlsen:
 I know that was redundant but I think limb design has a lot to do with performance and one bow of equal weight at 28" may actually outshoot a bow of equal weight at 31". [/QB]

X2 A good bowyer can design a bow for a short draw that will lose little if any efficency.