Arrow weight vs length

tel

Active member
Fonz Awardee
I've been having a little ponder. If you were weight matching arrows and found minor discrepancies in length would the weight be the main criteria? ie is it better to have closely matched weights and not so critical length or the other way round?
 

Marcus26

Well-known member
compound you can cut to differennt lengths, but you are better off adding or removing weight to/from the point than cutting the shafts
 

buzz lite beer

Well-known member
What sort of minor discrepancies are you talking about as little as 5 grains difference in weight should mean about 4cm lower than the lighter arrows at 70m (found this out by accidentally putting an old pile in an ACE that had a heavier insert in it was consistently lower than my group) Length, however is more critical if a clicker is being used, the weight of shaft unless grossly longer or shorter will have little effect on impact points if shot from a compound or non clicker shot recurve.
 

tel

Active member
Fonz Awardee
To clarify: what started me wondering was when I thought I spotted a couple of arrows in a set just slightly longer than the rest, but only a couple of mm at most (as it happened I then decided it was because they weren't all upright, but I need to check again).
I am talking recurve and I do use a clicker.
 

buzz lite beer

Well-known member
I would say that discrepancies that small would show little/no adverse effects in grouping performance and greater deviations are achievable by human error alone. Another thing I have found is that even the position of fletchings makes little difference to groups, had a set of X10's with spinwings moved near to rear node of arrow (alleged to increase stability) and the other six fletched as recommended 1" from end of shaft, no impact difference whatsoever and no difference in group size.
 

tel

Active member
Fonz Awardee
Thanks buzz - so as far as matching is concerned it would still be better to keep the weights tight?
 

buzz lite beer

Well-known member
Well it's best to completely eliminate as many variables from both equipment and shooting form as possible, However it's so easy (I know) to fill your head with problems that aren't really that much of an issue, I have heard of archers weighing individual components of arrows, filling piles down (without anaesthetic) even trying to presicely match the amount of hot melt glue used on points, Who can shoot so well that that's going to make a difference ?
 

Marcus26

Well-known member
Um, you would be suprized.
A new set of high end arrows would often have a 1 grainvariance between the set. The points could be the same. This could lead to a +/- 2 grain variance in a set. (I have build X10's that would have been +/- 3grains had I done it randomly)
So for a 2 grain variance on a compound bow with a speed of 265fps you would get a 24mm difference in impact point at 70m. For an average shooter (325 at 70m scorer) this will impact on the score for that shooter.
90m and that would be a 42mm drop. That's huge! Will keep you under 300 at 90m which is out of 1300.
For recurve the bow is slower so the impact is greater.
For a 195fps recurve bow with the same weight variance that 2 grains will make a 68mm difference in impact at 90m and a 39mm difference at 70m. Enough to impact on the scores of even a 1000 recurve shooter.

How to weight match correctly

Go out and buy some grain scales, make sure they go to 0.1 of a grain. (many are only 0.2 or 1.0)
Cut all your arrows to the exact same length
Weigh all your shafts once they are nocked and fletched
Weigh all your points
Match the heaviest point with the lightest shaft
That should get around 9 of the dozen exactly the same.
For the others if they are far out ( > 1 grain) then either file the point if to heavy or add tin foil to the shaft for too light.
Re weigh after gluing in point and they should all be well within 0.3 of a grain.
For 1 hour's work you may pick up ALOT of points.


Well it's best to completely eliminate as many variables from both equipment and shooting form as possible, However it's so easy (I know) to fill your head with problems that aren't really that much of an issue, I have heard of archers weighing individual components of arrows, filling piles down (without anaesthetic) even trying to presicely match the amount of hot melt glue used on points, Who can shoot so well that that's going to make a difference ?
 

tel

Active member
Fonz Awardee
Thanks Marcus.

I'm not in your league, but an extra 15 points on a fita yesterday would have made my season (shot very mediocre 90m, bloody awful 70m and ended up having to 'best' both 50m and 30m to be in with a chance of my aim for the day, my first star....15 points under!).

It may well be that a better matched set would have made a difference, though I did use the closest matched half dozen of the set.

Still wouldn't have stopped me shooting like a muppet though!

tel
 

wingate_52

Active member
Thanks for the specific info Marcus. Data like that cannot be argued against. If your arrows are not matched, you are not going to do as well as you could. Off to add weight to my Fatboys, and carefully weigh out my hotmelt glue.
 
D

Deleted member 74

Guest
It wasn't until I weighed my X10's and found them to be 2.5 grains variance across the set, pulled them apart and rebuilt them with a 0.2 grain variance that I shot my first 1200 FITA in a tournament. My groups were very noticably smaller at 90m and 70m. I also got my first 6-gold end at 70m.
It does make a huge difference!
I wouldn't shoot a set that was more than 0.5 grains difference. I especially wouldn't shoot a set from a recurve that had different length shafts.
 
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