August 22nd, 2009, 02:44 AM
Arrow spine: Too soft, too stiff?
I have been shooting my Reflex Caribou the pas couple of days and boy, does it shoot well. I have been shooting it @ 29" @ 67#, the tiller set exactly @ 8 7/8". The bow draws smooth shoots very well. My arrows when shot through paper suggest they are a bit too stiff. They are 30" XX78 2219's with 3-5" feathers, 145 grain points.
Now, when I shoot them bare they cannot help but almost end completely sideways, nock left, suggesting they are underspined? This is without anything to compensate for the lack of feathers, which I was under the impression should be VERY close a an arrow w/ feathers.
Now, I am running out of draw wieght and I prefr not to crank her up anymore, however my question is, are my arrows too stiff or too soft? I'm assuming the later, but, why would they be so off when shot bare? The only option I have to soften the spine of the arrow, would be to make them a little loner, maybe an inch or a half? I tired adjusting the tension on my NAP Plungerest, but, it didn't seem to make any difference or atleast not @ the short distance in the basement. Centershot was set using the "french tuning method".
I'm looking for suggestions and as always, it's greatly appreciated.
August 22nd, 2009, 02:58 AM
A quick and easy check, is to change field tip weight. Drop down to 100 grains, if that doesn't show a change, check your center shot. I wouldn't think that your set up would be underspined, though.
On a side note, how old are the arrows? May have the spine shot out of them.
August 24th, 2009, 09:16 AM
Yup, what Fingerflinger says. I don't know how old your arrows are but 2219's are pretty tough so I suspect those 145 grain tips are what is throwing off your tune. An easy check would be to take two turns off each limb bolt and see what happens.
August 24th, 2009, 11:48 AM
You could try moving your rest slightly out away from the riser. Correct me if I'm wrong here, but if your arrows are acting too stiff you need to add point weight not subtract it.
August 24th, 2009, 05:17 PM
Been there, done that. If you shoot ALOT, it doesn't take much time to do so.
Originally Posted by fingerflinger
August 24th, 2009, 07:13 PM
These arrows are only a few months old. I only had 3 cut @ 30" so I'll either have the others cut @ 31 or 30.5". It is very close. I actually have one arrow that is missing quite a bit of feathers and it leaves a bullet hole. The other has more feathers, make the spine stiffer and makes it look like two bullet holes side by side connected by a tear.
As for the bare shaft, it seems to be hitting a little better, but, still showing soft. This is strange to me. If I could find 150 grain heads, I may be able to stick with the shafts I'm using.
I'm still loving this bow and think it is an excellent finger shooter.
August 24th, 2009, 07:41 PM
Nock left bare shaft is too weak a spine. When I set up a bow for fingers I first set my centershot so that at arms length and the string is inline with the limbs the same as where it comes off the wheel, the arrow tip will angle to the left of the string with 1/8 to 1/4" of daylight between the string and the tip as viewed. I then set tiller for my low grip at 1/4" closer on the bottom limb. Then I set my nock height. Assuming I've already set the bow near the poundage I want and the arrows are within that range for spine I shoot a bare shaft at 10ft. If the arrow dives to the right with the nock left I need to reduce the poundage or lighten the tip. The reverse is true if the arrow goes right. Once I get the arrow entering straight in I back up to 20 yds. I make adjustments there so the arrow flight is clean and then I back up to 30 and do the same and then even 40yds. A good friend of mine and a national and world champion, Vince Hershell, once told me that he prefers the bare shaft to hit slightly left and down from a fletched shaft as he felt it allowed more forgiveness than them hitting the same place. I find that this is exactly what happens when you don't put tape on your arrow to match the weight of the fletching so I don't worry about it. You are so close anyway to the same tune, within 1/4 turn of a limb bolt. An interesting thing about in and out rest adjustments, they just seem to make the arrow hit left or right without disturbing the clean flight of a bare shaft. It's poundage and/or tip weight that affects how clean the arrow flies.
August 24th, 2009, 10:28 PM
Try lighter points
2219's are pretty hefty all around, weight and spine so try smaller weight points to see if that helps. I'd also say they might be to short for a 29 inch draw making them stiff.
Also guessing the Caribou is center shot at 3/4 inch from riser, so a tad more out should give you a good start for archer's paradox to work for a finger flinger.
August 25th, 2009, 10:07 AM
I made a mistake in that last post. The bare shaft should hit slightly RIGHT and low of the fletched shaft.
August 25th, 2009, 07:57 PM
I tinkered last night to get it to shoot bareshafts and paper tune correctly. It seems with the way it was set up, if I shot it with 100 gr. points, it bareshaft tuned correctly. However, I would like to use @least 125 gr. points, so I'm going to turn the weight down until it bareshaft tunes.
However, how much longer do you think the shafts would have to be to keep my 145 gr. points? They are currently 30" 2219 @ 67# w/ 3 feathers. Currently I have a little more than an inch of arrow hanging over the Plungerest @ full draw using the berger hole nearest to the front to the bow.
August 25th, 2009, 09:43 PM
Ok, tinkered some more and used the black spring on my NAP Plungerest, which is the stiffest and turned her all the way stiff. Using the 30" 2219's w/ 145 gr. field point they are just slightly underspined still @ 65#. I would like to take a 1/4" or more off and see how that works. Then I could incres the weight a little more too and back off on the plunger.
I appreciate the help fellas.
BTW, the bareshafts are hitting about an inch low and to the right.
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