Trad. recurve nock point height?

Andyt23

New member
I shoot a Bodnik Mohawk traditional recurve (37.5# @ 30.5") split finger with a glove - and I'm trying to set up some new arrows...

I've been using Easton power flight 400s, with 125gr points and 5" feathers (that I was previously using at 45# on hybrid limbs, same bow, with 80gr points in), and I find them heavy and a bit stiff for the lighter bow. So...

I'm moving to Bearpaw Penthalon Slimline 500s with slimline break-off 125gr (nothing broken off) points, slimline nocks, 3" feathers and cut half an inch shorter than the power flights, in an effort to regain some of the speed I had at 45# - and that's working out great.

I think the spine of the arrow is okay - they're going right where I point them around the 3D course at a good range of distances, and the bow is much quieter with them too - but I was getting porpoising at the same nock point height of 5/16" as the power flights. Adjusting down (for the slimmer arrow..?) didn't make any difference, so I've gone up and it's only at a full 1/2" above square that the vertical movement is noticeably reduced, and they fly better again if I turn the index feather in rather than out. And it still could be a bit better really.

As I say, there's no side to side movement that I can tell (maybe just because they are going up and down so much?), but that nock height seems very high to me, especially as I feel I could go another 1/16 and improve it further. Is it too high?

Could spine be an issue? I've got some leeway with point weight and shaft length (I've only cut and fletched two so far), but I don't want to start messing with them if that isn't the problem.

thanks in anticipation
 


KidCurry

Active member
I think my first step would be to bare shaft test to see for certain what is happening and also look at the FOC to make sure you are not too far forward.
 


Andyt23

New member
Thanks I'll check those things out :thumbsup: Can you recommend a good distance for bare shaft - is 20 yards okay or should I bring it closer?
 


Lammas

Member
I would suggest at least two distances, like 10 and 20 yards.
If the arrow is still fishtailing and you hit the zero-crossing point of that oscillation, you fool yourself.
 


Timid Toad

Moderator
Staff member
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Ironman
Yes, the further away you can get and still be confident of your accuracy - if you were a sighted recurver I'd recommend 30 yards. If you can manage that it would be perfect.
 


Andyt23

New member
If the arrow is still fishtailing and you hit the zero-crossing point of that oscillation, you fool yourself.
Don't understand what that means... but I can certainly try a couple of distances and see what happens. thanks
 


Andyt23

New member
Yes, the further away you can get and still be confident of your accuracy - if you were a sighted recurver I'd recommend 30 yards. If you can manage that it would be perfect.
hmmm, might be possible if I set up a point of reference instead of the usual instinctive shooting and repeat it lots to get some reliable feedback - and I can always walk forwards until I'm comfortable, but knowing that further is better is useful thanks.
 


albatross

Supporter
Supporter
Don't understand what that means... but I can certainly try a couple of distances and see what happens. thanks
I think it means that with any oscillation (porpoising in your case) there is a 'changeover' point between left/right or up/down where the shaft will be in-line (straight). You might just be unlucky enough to hit that point as your arrow strikes the target. This could lead you to believe you have 'cured' the problem, but you have not. Ain't tuning fun!
 


Timid Toad

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Staff member
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I think it means that with any oscillation (porpoising in your case) there is a 'changeover' point between left/right or up/down where the shaft will be in-line (straight). You might just be unlucky enough to hit that point as your arrow strikes the target. This could lead you to believe you have 'cured' the problem, but you have not. Ain't tuning fun!
And, coupled with the principle of "that's near enough", it's a lot more common than you'd think.
 


Andyt23

New member
I think it means that with any oscillation (porpoising in your case) there is a 'changeover' point between left/right or up/down where the shaft will be in-line (straight). You might just be unlucky enough to hit that point as your arrow strikes the target. This could lead you to believe you have 'cured' the problem, but you have not. Ain't tuning fun!
Ah right thanks, and presumably that's less likely to happen at multiple distances? I'll keep it to level ground shooting then so shooting angle isn't a factor either.
 


geoffretired

Supporter
Supporter
If you shoot bareshafts, as suggested by KidCurry, there will be no oscillating. You will see the arrow diving down and continuing to dive, or climbing and continuing to climb.
 


Andyt23

New member
If you shoot bareshafts, as suggested by KidCurry, there will be no oscillating. You will see the arrow diving down and continuing to dive, or climbing and continuing to climb.
Ah I see, so that's without the feathers trying to stabilise the shaft and over correcting - I was going to research all this as I've never done it before so I also don't know how to interpret the results.
 


geoffretired

Supporter
Supporter
The bareshafts will continue in the way they leave the bow. If the tail is too high on the string, the arrow will be launched with the tail trying to roll over the top of the point end. Or put another way, the point will fall quicker than the fletched arrow in level flight.
If that happens you will lower the nocking point and try to reach a stage where the bareshaft lands almost with the fletched ones, or just below.
 


Andyt23

New member
Thanks Geoff, I haven't had a chance to shoot yet (hopefully tomorrow night) but I have calculated the FOC of a fletched arrow at 14.5%, which from what I can find out seems to be at the high end of normal?
 


geoffretired

Supporter
Supporter
In the days of ally arrows and not much else, the points were described as 7% and 9% for target archery.
That was the FOC % and 9% was considered to be the heavy point.
Compared to that 14% seems a bit front heavy but depends on the shafts according to Easton.

A/C/C Target Arrows 9-11 %
A/C/E Target Arrows 11-16 %
Hunting Arrows 10-15 %

Not sure what Powerflights need.
 


Andyt23

New member
In the days of ally arrows and not much else, the points were described as 7% and 9% for target archery.
That was the FOC % and 9% was considered to be the heavy point.
Compared to that 14% seems a bit front heavy but depends on the shafts according to Easton.

A/C/C Target Arrows 9-11 %
A/C/E Target Arrows 11-16 %
Hunting Arrows 10-15 %

Not sure what Powerflights need.
I see, so I should find out the recommended range for the arrows is (Bearpaw Slimline)
 


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