Bow poundage vs. wooden arrow spine?

wully

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So I'm looking forward to the winter projects list and one of them is making up some arrows to replace the sad, smashed remnants of the summers shooting..

Currently I'm shooting 11/32 shafts bought for a 45lb recurve since sold. I'm now shooting a 35 lb bow and much happier with it. I'm thinking of going down to 5/16th shafts and they seem to be sold in 30-35 lb or 35-45 lb spine - since my bow is allegedly 35 lb which range would be best?

I guess the smart way would be to borrow a draw weight scale and see what I'm actually holding at my draw length then choose?
 


Timid Toad

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Hmm. Not that simple. Yes you do need to know the poundage on your fingers, but it also depends on the style and make of bow you have. I know Border flatbows (with no glass and only wood and carbon construction) need to go up, sometimes several spines. My English longbow needs me to go down a spine group. So if you are shooting recurve you'll need to factor in the limb type and construction. Now, how did the shafts you had match well to your 45lb set up? That should give you an idea of how efficient or not your style is. Sloppy looses, string catching clothes and arms etc will all make your bow less efficient.
Personally, if I'm shooting shorter distances I want the most robust arrows I can get, so the fatter the better. If I needed 100yds I might look to skinnier ones.
 


Del the Cat

Well-known member
Poundage is only a rough guide.
It depends on the type of bow.
1. Does it have a cut away for the arrow, e.g near centre shot? The closer to centre shot, the stiffer the spine can be, an English longbow nees a more flexible arrow as it has to bend round the grip.
2. What's it made of? If it's made of modern materials with some recurve or reflex rather than a wooden English longbow the cast will be a little faster and it will want a stiffer arrow.
3. Arrow length and point weight also matter.
You will probably be fine with 30-35 spine 5/16 shaft 100 grain point as a start point.

It's less critical that a lot of people imagine... the important thing is that your arrows are reasonably matched, you'll soon unconsciously make any slight adjustment needed once you start shooting them.
BTW. I use the same arrows for for bows (wooden bows) from 35# up to about 55# heavier than that and I go up to 11/32" shafts which adds some extra weight and stiffness.
Del
 


wully

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I’m shooting a 35 lb Bear Super Grizzly and it shoots the 45 lb 11/32’s OK apart from the observation that a longer ranges the arrows drop suddenly instead of a more even trajectory which is why I thought I’d try some 5/16” and lighter points..
 


Del the Cat

Well-known member
I’m shooting a 35 lb Bear Super Grizzly and it shoots the 45 lb 11/32’s OK apart from the observation that a longer ranges the arrows drop suddenly instead of a more even trajectory which is why I thought I’d try some 5/16” and lighter points..
It's easy to forget that most of the weight is in the shaft. Going to 5/16 is a good move. Not much to gain by going lighter than 100 grain points.
Look at fletching size too, not advantage in going over 3" long, unless the arrows are so ill suited to the bow that they need straightening up quick!
Del
PS. The "sudden drop" at long range is just an optical illusion, the trajectory is pretty much parabolic, it just gets foreshortened at long range from the archers viewpoint.
 


another thing to consider is your draw length. The designated spine is generally at 28" so if you have a long draw you can reduce the weight of the point. I prefer 5/16 shafts as you have less drag and thatgives you a slightly flatter trajectory and further distance is needed. there is an advantage to a fatter shaft at short range, you smash them up slightly less
 


Lammas

Member
As mentioned before, 35lbs is not always 35lbs - the type of the bow and "center cut" play an important role, too.
A bit of experimentation might be at hand. I used to get full length shafts, and shortened them until I got adequate results.
Surely one can easily adapt to left-right deviations. But excessive waving of unmatched spine will eat the arrow energy away, with an large drop over greater distance.
Tried my horsebow 35-40# cedar arrows (32", 70gn tip) last weekend with my hunting recurve (Samick Lightning, 30lbs), and the work fine (at least for me).
 


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