Ryoon, I appreciate your comment, as it's thoughtful. and thought provoking.
The length of the limbs doesn't affect the force on the handle, even though it would seem intuitively that a longer lever will produce a stronger force. That can be true of a lever in an unlimited mechanical sense.
But in the case of a bow, the force at the handle is actually always limited by the bowyer during construction to the draw weight he/she intends. The force applied by the bowyer's hand to the handle of a 50 lb draw bow is 50 lbs.
That is true whether the bow is 48" or 76" in length. What varies is the force applied at the tips of different length bows of the same draw weight. That compensates through tillering to yield 50 lbs at the handle on a 50 lb bow.
re. handle shape. : I agree with you that the shape of the bend in the handle of this bow is not quite the same as some illustrators have drawn of the original. But most of the handle is missing on the real bow, so those are necessarily guesses as well. The bottom of the original is completely gone. And that's probably why it broke.
The bottom of the handle I decided on is, I'm guessing, deeper than the original. I did that intentionally. This isn't a strict reconstruction, but it's closer than the straight handles usually seen on reproductions.
re. wood: I don't know what the quality of yew used in the original was, but references say it was all heartwood and in photos, highly violated. I wanted to try this bow in red maple to see if lighter limbs would yield somewhat better performance than one other reconstruction I read about. And because I've grown and cut it myself. here That was also a personal choice.
Asharrow, I agree with you totally. I didn't intend this to try to prove anything in archaeology. But just to do some things I'm curious about and have fun while doing it.