An Archer was born

Once upon a time, a fellow Trad Gang member from Norway reached out to me while anxiously awaiting the birth of his granddaughter 9 years ago….He said he would love to see her born with a bow in her hand, and asked if this is something I could do? I told Trond I would be delighted to build something special for his new grandaughter.

 So I rolled up my sleaves and built a little self bow from maple. I had so much fun with the project, I had to build arrows and a quiver to go with it. It’s 24” in length nock to knock.



 

The day a proud Grandpa Trond was looking forward too finally arrived, and he presented baby Thea Louise her first bow on the day she was born…


 

Well little Thea Louise didn’t take long to start growing up……Here she is at 1 years old getting a feel for her first longbow…
 





Here Is Grandpa Trond showing her the stump shooting trail ….



 


Another year passed……… and little Thea at age 2 she needed something a bit  more practical than her first longbow to consider using for her  training to come…. In 2015 I had just come up with a miniature Recurve design that I thought might fit the bill nicely.  I designed this little bow to replicate the old 60’s design recurve, and these run 37” nock to knock in length.


Here is Thea at age 2 checking out her first recurve bow…


 

And here she is trying to figure out how this thing works…




 

 

To be continued  shortly….

Kirk, we posted at the same time 
So case in point OP ...... listen to Kirk and the other great bowyers we have hanging around here ....... lucky to have them 

All bows are not created equally, and you will have a lot of different answers to this question that will mostly be speculation. Draw weight and energy storage, vs how much energy actually gets transferred to the arrow totally depends on the bows limb design.

Even using the same identical bow design in different draw weights can make a big difference even if the GPP (grains per pound) are closely matched. I can give you a good example...

Take an ASL design bow with very low preload in the limbs. These bows draw very smooth in the first few inches of the draw and slowly gain pounds per inch throughout the draw cycle. These bows typically have very poor performance in lighter draw weights compared to higher preload limb designs like some recurves and hybrid long bows do....  But... once you start increasing the draw weight on these ASL long bow designs, the performance increases a lot due mostly to higher preload, or more tension on the string at brace.

One of the key components of a bows performance is not just how much energy is stored in the limbs, but how much of that energy is transferred to the arrow. Some bow designs are much higher in performance than others, but even high performance designs have different performance levels depending on draw weight. for example... a 30-40# high performance recurve or hybrid bow shooting 300 to 400 grain arrows. (10 GPP) drawing 28" will have significantly lower performance than that same exact limb design at 50-60# draw weight shooting 500-600 Grain arrows. The heavier limbs with heavier arrows may be 10-15 FPS faster in some cases.

Why?   I could write a full chapter in a book explaining the details, but the bottom line is the ratio of limb mass to preload is much different, which results in less energy being transferred to the arrow. or simply put... it's the lower draw weight limbs not having enough string tension at brace to stop the limbs clean and transfer the same amount of energy.

You can get into some other of the same factors with longer draw lengths vs shorter draw lengths and different limb designs too....   

So to answer your question, there is no rough formula with so many different factors involved.

Kirk

If you use the same gpp, arrow speed shouldn't change much at all as bow weight goes up, all other things being equal.  You will be shooting progressively heavier arrows at the same speed. I've read, but haven't tested, that a# of bow weight increase yields a 1-1 1/2 fps gain in speed. I don't know if those who offered that figure accounted for a change in arrow weight.   

Glad you guys survived the storm without much damage!