Primitive Archer
Main Discussion Area => Bows => Topic started by: jameswoodmot on January 10, 2026, 05:46:13 pm
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Having had no interest in short draw bows, Native American bows, arrows and quivers turned up today, now I want to make a short bow!
I’ve got quite a few short elm staves that should be ideal for this but it’s lead me to wonder about the trade off between draw length and draw weight.
If I’ve got 50 something inches of wood I can either tiller to a low poundage at a longer draw length or a higher poundage at a shorter draw, how do I know which is going to give me the best arrow speed for that stave? Somewhere there is a sweet spot in the middle but is there any way of getting a rough calculation? I suspect there are too many factors for it to be viable to work out.
I have only ever got a bow to my draw length before and just let it turn out at the poundage it wants to be.
Is it know what sort of poundage and/or draw length any of these bows were historically?
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Short bows... my favorite 😍
Im decently studied up on them and have made a few over the years. A couple are pretty fast. Ill tell you a few bullet points on short bows.
Short bows are not limited in their draw length and weight by nature of their length alone. Their width and amount of recurve at the tips make up for the rest of the equation.
A 50 inch bow can pull all the way to 26, even as a stiff handled bow if the handle is its smallest size, the tiller is good, and the tips have enough recurve to keep the string angle down from stacking.
It can have any draw weight you desire as long as there is enough wood in the bending section to absorb the bending stresses. This is controlled by how wide the bow is made to be. By nature of how things work, a 50 pounder will need to be twice as wide as a 25 pounder with all things equal, because two 25s equal a 50.
So, your stave width will be your primary limiting factor.
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Fantastic, thanks Sleek
So with the bows in the book, the length and width are listed. Lots of them are only just over an inch wide.
If I wanted to make a replica of one with very similar dimensions, the higher the poundage I make it the shorter the draw length will have to be to prevent it taking loads of set or snapping.
If I were to set the limiting factors to those dimensions, I can vary the draw length and weight within reason. Is a lower poundage at a longer draw going to give more arrow speed than a higher poundage at a shorter draw?
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Set only happens when a bow has too much draw weight for its working limb volume. Its not related to its draw length, even though thats what is commonly blamed for set.
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I’ve removed what I just wrote, let me think about this a bit the cogs are going
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Ok, I’m up to date on the volume thing.
Question stands about finding the sweet spot with draw length and draw weight.Or draw weight and limb volume, if that is another way to put it.
Increasing the draw length, I will have to decrease the limb volume to maintain a suitable volume to draw weight ratio. Which in turn means I will be continually decreasing the draw weight as the length increases
A bow with set length and width, I assume, will have an optimum where the draw length is long enough to have good power stoke and the draw weight is high enough to be storing a good amount of energy. Beyond experience and trial and error is there any way to calculate that optimum?
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This is a good question. You could probably approximate this by drawing out some FD curves at varying draw lengths and poundage’s and seeing how energy storage compares. There’s probably a ratio where the draw length and draw weight can change proportionally to make equal energy storage at any given combination. My guess is that maximizing draw length is more important for transferring that energy storage efficiently.
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Good questions. Good advise from sleek. I’ll throw this wrench in all this. I made two shorty bow. Both 45-50lbs. Both bendy d style Osage bows. Both from same tree. In fact both were narrow sister splits from same short stave. Both had same dimensions of 50”ntn about an 1” wide. Both had small steamed recurved tips. Both seemed to be good till it wasn’t. One took set and then exploded at 26”. The other one is great. Little to No set yet and plan to finish it up for a 26-28” draw. I’ll post some pics here of it when I get back to it. And if it survives. I have other pressing projects on the go. lol. My point is that sometime we can do everything right and the wood has other plans. I’m sure there are rule of thumb methods to follow when it comes to short bows and even bendy handle bows. That will give you more certainty moving forward. The other thing that can be done for shorter bows to extend their draw is sinew. If done right a little does the job of extending your draw length with a measure of safety.
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I kept records on all the short bows I made, then plotted them on a spreadsheet, and found they followed predictable patterns. I found a came up with a formula that works with them and have used that formula to design my flight bows, with good results. Recently I built a simple program that will give you the predicted set a bow will take based off its working limbs dimensions and its draw weight. Im hoping to attach that program to this site as part of this years upgrades. But im happy to help run some numbers for you if you like.