What affect does riser length have on bow performance and bow weight?
Longer riser same stack heavier draw weight. More or less working limb for different draw lengths.
It's totally dependent on total bow length as far as draw weight goes. Let's use std ILF riser lengths for example. 15, 17, 19, & 21". If you use medium length limbs on all of them the length and have 50 @ 28" on the 21" riser you will have a 64" bow length .
Using the same limbs your draw weight will increase between 2# & 2.5 # as you shorten the bow length depending on limb length.
19"= 62" length= 52.5#
17"= 60" length = 55# ,
15"= 58" length = 57.5 @ 28".
The most common ILF limb lengths are medium and long limbs, but they do make short limbs too.(they are not very common) The long limbs are 1" longer than the mediums. So a 19" riser with long limbs will be 64". The longer limbs have more draw length potential and are smoother drawing using the exact same design and taper rates and just lengthening the butt wedge length. Maintaining the same string nock location on the hook will insure comparable performance rates. The difference in draw weights with long limbs are closer to 2# for every step down in riser size too.
Btw... riser length has nothing to do with bow performance... period.
Hope that helps. Kirk
Thanks guys::
What longer risers DO have is more mass weight, and a taller sight window. which is very desirable for some archers.
i've always used 18" on my longbows so was just wondering how shortening the riser would affect draw weight. I wanted to get some idea before I wasted material.
I think like Kirk's ilf it will be about a lb per inch of riser less to be shorter
Quote from: hunting badger on September 13, 2025, 12:46:45 PMi've always used 18" on my longbows so was just wondering how shortening the riser would affect draw weight. I wanted to get some idea before I wasted material.
If you shorten the riser an inch, and use the exact same limb form and stack height, you can shift the wedge stop in your form a 1/2" to compensate for the shorter riser length and get pretty darn close to your same draw weight.....
but before you do that, you might just want to try relocation of the tip notch first. Sometimes that longer limb can make an amazing difference.... Then come down an inch on each limb and make another set of tip notches. That will give you a whole different limb dynamic, with a 2" shorter bow length.
After doing that... shift the limb stop another inch on your form, and do it again. You'll have 4 different bows with different performance levels... it's never ending until you say close enough. :biglaugh: