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Grantmac
01-07-2010, 09:34 PM
This one is for the stickbow shooters.

It's getting to be time to reserve my string. I know that I can drop a few grains out of my string by serving less of it (the stock serving was very long) and switching to a tied-on string nock.

My bow tends to have just a little bit of handshock and quite a bit of vibration/noise. I'm shooting lightweight (relatively) arrows for target work, with heavier hunting arrows it's fairly smooth.

The question is whether loosing a few grains from the string will increase or decrease handshock. I know it may be very miniscule but I'd like to know what to expect if I try to keep as much weight out of the string as possible. I know a lighter string will increase efficiency, but for now lets just talk about feel.

Thanks,
Grant

Bow Walker
01-08-2010, 11:01 AM
Good question Grant. Lightening the string could go either way (I think), it could increase your felt hand shock/vibration/noise because you've got less weight/mass pushing on the lighter target shafts.

Or. It could do the opposite. It could be that lightening the string mass will bring it more inline with the lighter target shaft and thus produce a bit less shock/noise.

Although I do think that the few grains that we're talking about here will not make a difference that would be noticeable.

Why not shoot the slightly heavier shafts and get rid of the noise/vibration altogether? I suspect that the loss of a few feet in velocity will be much better for the limbs of your bow anyway. I'd worry about that vibration and shock doing damage - over time that is.

Plus, by shooting the heavier 'hunting' shafts at targets and 3D shoots, you'd be right there in terms of accurate shooting when it comes time for hunting - having shot the same weight shafts all during the off season.

Hope this makes sense. Probably I'm spitting into the wind (again) and will be corrected by wiser minds than the one I currently use. But. That's how we learn - or at least that's one way of learning....

Grantmac
01-08-2010, 01:26 PM
Just for the record, I've shot much more shocky bows then this one. It just tends to act a bit like a tuning fork. So far an increase in brace-height seems to be making it a little sweeter and I'll be experimenting today a bit more.
I've lost a barely decernable amount of speed with the higher brace but it's gained a far amount of forgiveness. Thats a trade worth making in this case.

I'll update after I re-serve the string. For now lets see if the gurus can come-up with anything concrete on this.

-Grant

Bow Walker
01-08-2010, 01:43 PM
Brace height. I forgot about that. The sweet spot for the brace on my long bow is between 6 5/8 inches and 7 inches. Amazing the difference that it makes (once I remembered the shooting-in process).

I'm currently messing with the nock point position, looking for the best flight spot on the string. Then I'll do the center serving and make a permanent nocking point.

Right now it's P-ing rain out there. I'll wait for better weather.

Onesock
01-08-2010, 01:51 PM
A stick bow will shoot its fastest at the lowest brace height possible. This maybe the fastest but not necissarily the best brace height. You have to find the sweet spot for the brace height which only you will know. I would serve the string back to its original serving length. You can't shoot well enough to ever tell the difference between the weight of a short serving or a long serving:-D. I agree with BW about shooting the heavier arrows, it will lessen the hand shock. The few ft/sec you gain shooting the light arrows will only hinder when you load up the heavy arrows for hunting.

Bow Walker
01-08-2010, 02:52 PM
Hmmm, Onesock agreeing with me?!? Oh, oh.

I certainly do agree with him regarding "not being able to shoot well enough" to tell the difference between a few grains of string weight though. All I have to do is to step back to 20 or 25 yards and fling a few arrows with my long bow. That shows me (graphically) my shooting expertise - or lack thereof!

Grantmac
01-08-2010, 07:58 PM
Well I did a quick search over on Tradgang and it looks like a lower weight string definitely will not increase the handshock.
I know I can tell the difference adding a brass nock makes on some bows so I'll see if taking it off this one can be felt.

I realize that going heavier on the arrows is an easy way to remove a bit of handshock. I find heavier arrows make much less difference compared to a change in fletching. I just switched to offset from helical (and 5" to 3") and it's made a major improvement at long range. The flip side is that I have to be very careful to avoid torque and my set-up now seems to require slightly more spine. I think I will have to find some way to get a little weight into the back of the arrow to increase both weight and spine.

-Grant

Bow Walker
01-09-2010, 11:41 AM
Grant - are your arrows within the correct weight ratio for the poundage of your bow? Just a thought.

Perhaps you can increase the nock-end weight by going to some sort of a "pin nock and bushing" system such as those offered by Gold Tip.

http://www.goldtip.com/nocks.htm

I use the pin nocks and bushings on my compound hunting arrows and they work great out of that setup.

Grantmac
01-10-2010, 06:25 PM
Well I decided to do it right and made an entirely new string. Bit apples to oranges as it's endless loop vs. flemish. The original string was 16 strands.

The new one is a 10 strand FF flemish twist padded with 6 strands of b50 in the loops and double served with Diamond Braid (.022 I believe) with just enough serving for tuning.

The bow is noticeable quieter with less vibration. Arrows seem to flying a little quicker too, but I'll need to get out to the range to verify that.

I definitely think that I need to look at adding a little weight to the arrows. I'm actually thinking that a small press-fit piece of dowel in the back would work fairly well. I think that I'm on the low side for spine so that would give me a little extra there too.
The bow is pretty nice to shoot now but a little more weight and spine should make it more forgiving.

I did raise the brace-height with the old string a good amount and that helped a lot too.

-Grant