Hi guys! Just switched from cables and pulleys to a Martin Hunter #50. I draw 30 inches. I wanted to confirm my actual draw weight and invested in a bow scale. After calibrating it against a know 30lb weight, I was surprised to see that I draw barely 50lb at 30 inches. I let my son who draws 28 inches try it and it was about 45lb. Is it common to have the claimed draw weight at 28 inches out by 5lbs?
I don't think it is common for it to be under, but more common for it to be over. Does the weight on the bow show numbers with "X"s in front of it ?
Note too, calibrating it (scale) at one point means it is accurate at that point and not really at any other point. You normally need at least two points that bracket the approximate weight expected.
ChuckC
Check with Martin Archery they may very well measure their weight at 30" draw.... or is it marked 30@28?
are you measuring your draw length like this?
(http://i171.photobucket.com/albums/u301/kirkll/Drawings/Drawlength.gif) (http://s171.photobucket.com/user/kirkll/media/Drawings/Drawlength.gif.html)
Yes, it is marked 50# @ 28"and I did measure draw length like in the illustration. Repeatedly, I must say. To the amusement of my boys!
I will recheck the accuracy of the scale with other weights too.
Not common, but does happen. Like stated above, there is more than one way to measure DL, and that can skew things too.
Bisch
Will not call names but a few months back I pulled te easiest drawing 50# recurve I have ever seen,put it on a scale and it showed 39#.Checked 3 other bows and all were within 1 # of markings with the same scale.
Terry
I rechecked the scale with another reference weight and it is surprisingly accurate. Then went and marked an arrow at 28" and drew to that mark. Scale says 41# at 28"! Whow! Didn't think it will be out by almost 10#. Maybe something to keep in mind for guys who think about buying a 40 or 45# bow for hunting. You may have an illegal draw weight for your part of the woods.
I have a production recurve that missed the specified draw weight by about 5 lbs. My limbs were heavier than stated though.
It happens. Mine was a 3-piece, so the company swapped out the limbs for me.
I have a set of 45 lb limbs for my Samick Sage, draws 57 lbs at 29.5"
I've had too many bows that were under marked. I know this stuff can be a pain.
Maybe it was 50# @ 28" on their scale.
Could be difference between scales?
Could be difference between scales?
How old is the bow?
Is your 30" draw length from a compound?
It drops about 1.5-2" when you switch to longbow, depending on your anchor.
It has been my experience that most bows scale higher than marked on my digital bow scale by a couple of pounds. I have seen a few scale quite a bit higher than marked. I don't I have seen any bows scale under the poundage marked.
I've had them as much as 4-7# over marked weight. More then one or two!
Plus or minus 2# is a normal variance for all the bowyers I have dealt with over the years. I can't imagine that a custom bowyer would send out a bow without personally measuring the draw weight, and mostly they get much closer than that.
I would apply the same standard to factory bows, although I don't think they measure every single bow, but if it was off by more than plus or minus 2#, I would return it.
If your son is drawing 28" and you scaled him at 45#@28" with a bow thats marked 50@28, then that pretty close. Most bows will gain or lose 3# per inch.
QuoteOriginally posted by McDave:
Plus or minus 2# is a normal variance for all the bowyers I have dealt with over the years. I can't imagine that a custom bowyer would send out a bow without personally measuring the draw weight, and mostly they get much closer than that.
I would apply the same standard to factory bows, although I don't think they measure every single bow, but if it was off by more than plus or minus 2#, I would return it.
Martin is not a custom bowyer. They build bows in 5# increment. None the less, I would still return it.
QuoteOriginally posted by lablover:
How old is the bow?
That's a key question! I acquired a used howatt marked 55 @28 about 15 years ago. It scaled 50# at that time. Last year it scaled 45#.
since I started doing this I always came across people that said how smooth a certain bow pulled,,, turns out its smooth because its marked exactly what they ordered but pulls less poundage on the draw,,, 55lbs will always feel like 55# if its 74" ELB or a 44" KT44 it will feel like 55# trust your judgment,,,,, smooth is smooth and stacking is stacking but at the marked draw length poundage will always be poundage.
many bowyers will write down a weight that is off a few pounds just to keep you from returning it,, I've tried 11 custom bows once on a Laboratory scale at work that is calibrated once a month and all but one where marked wrong OR they some how dropped or gained weight over time,,,, I don't shoot a BW anymore but when I did that a Black widow was the only company who wrote down exactly what the weight actually was or they had a calibrated scale.
martin bows for me always had the wrong weight marked, my buddy's trad store right now has two brand new savannahs that are marked wrong, how can every bow be 50# on the money or 55# never marked 51-53-54 always dead nuts which is total BS.
First start with true draw length. Wrap a piece of tape around the end of the arrow at 28" and then draw it several times. Have your son or another person verify your draw. Then do the same with a scale. Most bow shops will do a draw weight check for you for free. If not free, find another shop.
So far as marked weight, it has been my experience that most production bows run 1-3# heavier than marked.
Even Border Archery will tell you that their bows will be within +/- 2# of ordered weight. That is supposed to be industry standard.
But then they mark them as true weight indicated by their scales.
Bow limb poundages are determined by the thickness of the laminations of wood and glass. The makers have a formula for lamination specs to be assembled in order to arrive at a certain poundage. If they thicknesses are off, then the poundage is going to be off as well.
One of the nice things about buying a bow at a reputable shop is that they will scale it for you if you ask...
The bow is brand new. It came from Martin, but via Amazon. Don't know if that makes a difference. We have tried all kinds of draw length tricks on it. I have checked my bow scale against a 30lb and 40lb dumbbell, which I also checked against a digital scale and everything seems accurate enough. Since I am drawing it to 50lb at 30", I am happy enough with it, cause I wanted a 50lb bow, but if I had a 28" or lower draw length I would have returned it for sure. It seems the opinion here is that it should rather draw heavier instead of lower, but in this case it seems to be way lower than indicated. Thank you to everyone for giving an opinion
I may phone Martin customer care about it anyhow to hear their opinion. Pity they don't seem to have email support because now I have to find a time that they are open and I am available.
Might be difficult to communicate since their factory burned down!
The AMO standards for marking bow weight allow some wiggle room, but not that much. For a bowyer, hitting an exact weight is a bit of science tempered with experience. It could be that the intended weight of the bow was to be as marked but somehow the maker did not check his final results. I'm not a professional bowyer, just a hobby builder, but I mark mine exactly as they scale.
If the bow is satisfactory, might just live with it.
BTW, this, below from Tajue above, is an accurate and vital observation regarding the physical sensation of drawing a bow. A bow that stacks has it's own distinct and unmistakable physical sensation as it is drawn but in the end, pounds is pounds.
Quotesince I started doing this I always came across people that said how smooth a certain bow pulled,,, turns out its smooth because its marked exactly what they ordered but pulls less poundage on the draw,,, 55lbs will always feel like 55# if its 74" ELB or a 44" KT44 it will feel like 55# trust your judgment,,,,, smooth is smooth and stacking is stacking but at the marked draw length poundage will always be poundage.
My experience in 13 years of owning Lost Nation Archery: 2 lbs off is common, 5+ lbs happens sometimes. (I even saw a 64" bow marked as 58".)
On stacking: it is my opinion that not all 50# bows will feel the same. I once took two bows that pulled 50# on the same scale and when pulling them I was absolutely certain one of them was heavier. The scale proved me wrong and the reason was stacking.
You might do better phoning the Canadian distributor although they might be a little reluctant to help with a bow that was purchased through Amazon.com
DDave