How do you all measure the draw weight of a bow? For example, you have a bow that measures 50#@28", explain how you would check that...
I had a conversation with a bowyer who does it in a way I had not heard of before. It makes sense but is not the norm as far as I know.
Since I don't have a bow scale I have a heavy rope attached to the rafters and hang the bow by the handle. I use an S hook on the string attached to a large WW2 ammo box and I fill the box with lead ingots (I reload) until it draws 28" from the string to the back measured with a tape. I then weigh the box on a floor scale.
I did one a few months ago and I got 65# and droptine59 measured it with his bow scale and got 63#. Pretty close.
Now what's your method? Don't make us wait.
It is not my method, but a bowyer's method. So how does this sound?
You pull the bow string typically with 3 fingers, right? So what he does is pulls the string with a block of wood shaped like 3 fingers to 28" on the arrow, and takes the weight measurement. This is in place of the typical "S" hook on the nock point of the string.
So what happens is, because your fingers are wider than that single "s" hook on the nock point, the limbs must flex more to get to 28" and thus the bow will register more draw weight with the block than the "s" hook.
So what do you think?? Is this normal or unusual? Now, in ordering a bow, I have to guess what the deviation may be so he hits my draw weight...kind of different.
This is only if my assumption is correct in that most standard practice is using the "S" hook at the nocking point when pulling the string.
Yep, most bowyers use some sort of a setup that holds the bow in place and then draw it with a hook tied to a rope, which is in turn tied to a spring scale. Sometimes just the spring scale S hook is affixed to the string and pulled. How much the weight measured that way will vary from the weight one would get by drawing with two or three fingers depends on bow length, design, weight and probably a few other things. In short, it doesn't amount to a hill of beans difference.
I draw mine with a spring scale, which has a single hook. I normally draw to 1/2" past the desired mark to account for the three fingered draw. Is it the correct way? I don't know, but it makes sense to me.
I thought it was odd because a bow marked 60# is 54# on a "s" hooked scale. This is what he said accounted for the difference. So, I want a 50 lb bow, not a 46# bow...so what do I order? Kind of different.
:0)
When I draw mine 1/2" past it only adds one pound. :)
What differences do some of you guys get. Does it make that much difference or are we splitting hairs. I would think that if the 50# bow feels and shoots good, whats it matter if it is measured with a hook or a gizmo.
someone will have a differeent idea then the next guy.I do use a block of wood the width and shape of my 3 fingers on the S hook of my bow scale.Yes it will make the bow scale read a little higher then the S hook does.I've never seen one like you mentioned gaining 6 pounds using a block.1-2 pounds is about normal with the block.Your only drawing the bow 1/2-1 inch longer with the block.bd
I would think that even with the block your bowyer mentioned you shouldn't get more than 2 lbs difference.
Keep in mind that not all scales read the same. Some bowyers also sometimes fudge a little if they miss weight.Instead of building another bow they just mark it as desired.Most bowyers also only guarantee within 3 lbs.Add that to any difference in scales and you could get a 5-6 pound difference.
AMO std. measure the weight from the deepest part of the handle to 26 1/4" if my memory is right. That should negate the differnece since you now have a fixed reference - all in all if 2 lbs of draw weight makes that much differnece I cannot see it. Good arrow flight is more important so it does nor matter what weight it is marked.
Overspined,
Sometimes the guy building your bow knows more than you?
I was ready to post a long explanation of how to measure draw weight. But decided it would only confuse the issue and deleted it.
If this is a big deal to you, why not ask your bowyer to measure the bow weight the way you want it measured? I'll bet you a dollar he'll do that for you especially when you tell him your concerns.
The differences should be very small-single point hooked on string compared to a three finger wide block. Your bowyer's method is fine but, unless the bow in question is extremely short, his weight variance explanation is awfully leaky.
Overspined, if a bow marked 60# scales out to 54# with the S hook, a six pound difference, one of two things is happening. The bow is mismarked and/or the scale is off. There's just not that much difference between a scale and finger hold.
thanks for all the input! I think I will just ask that he measure as I am used to. Basically, shouldn't there be a standard? That is what I was getting at. Why would each bowyer measure differently, regardless of scale being slightly off? Just seems that if I like a bow of a specific weight range, I should not ever have to guess how that weight is measured. That is all. Keep it simple, you know? I do think there is a big difference in how my release is between a bow in the 50# range vs the 40# range. Heavier bows tend to help rip the string out of my fingers for a cleaner release. So, I really WANT a bow the weight I ask for per the "standard" I am used to experimenting with...
I have a digital scale hard attached to the wall with the hook down, I put the string in the hook and draw the bow down until the back of the riser (the part away from the shooter) gets to a mark on the wall indicating the desired draw length. I look at the scale and record the indicated poundage, then a recheck a few times. I thought about the block of wood with a curve and string groove to simulate 3 fingers but a block of wood is rigid and people's fingers aren't, so that wouldn't help any. The hook works fine, I don't think anyone would want to split hairs over the draw wieght being a few onces off depending if its done by fingers or an 's' hook.
I have a question for Mad dog, if you hang the bow by the string aren't you adding the physical weight of the bow too? I always hang the bow on a steel peg, by the deepest part of the grip, then I will pull to 26 and one quarter inches, (which equals 28" of draw). I then use a loop of 1" mule tape hooked around the string (spread apart to simulate 3 finger spread) and hooked on the S of the scale. The scale is hooked to a ratchet strapped rope which I can pull down with my foot. I stop at the 28" mark and the ratchet keeps it there till I release it again. I do a draw force curve also, stopping at each inch of draw, and recording the weight. My bows are usually delivered to the exact pound of draw weight at the requested draw. Mike
Grizz, I got all that factored in.
Grizz, If you hang the bow by the string, you will indeed record the weight of the bow. However, the weight of the bow will also draw the string the equivalent amount. By hanging the scale from the string, you are also weighing the scale, but again drawing the bow the equivalent amount. Both ways work and with the same bow and scale, you will get the same reading.
Fletch, you have a very good point! Your last sentence is good enough for me, Both ways work!
I just went out and drew two of my longbows, one at 51 the other at 55# at 27".
I shoot one index over the nock and two under.
What I saw when I did this was that the bend point was around my middle finger. It makes sense since I put very little pressure on the other two fingers and there was virtually no curve around the group of three, just a bend at my middle finger.
I don't think there is any real difference from how I draw and using the s hook to measure.
You can actually use a bathroom floor scale. Use a 2x4 with a notch cut in one end and marked at 28". Put the bow string in the notch, set the 2x4 and the bow on the scale and reset it to 0 . push down on the riser to the 28" mark, should give you an accurate reading...PR
Quick, easy, and above all economical!