more bare shaft confusion

[Bladepeek]

I didn't want to hi-jack Burch's thread, but I'm sure confused. I used Stu Miller's dynamic spine chart and here's what I came up with:

My bow, 50# @ 28 (weighed). I draw 28.5", so it says I'm drawing 51.6#s at most.

I shot 2117s, 30.5", with 170gr Zwickeys, 26gr inserts and 20gr additional weight behind the insert. 3-fletched, 5" feathers. Seemed to shoot OK, and I killed a deer with the setup last fall (roughly 12 yd shot. I was fat, dumb and happy until I stripped the feathers off my worst looking arrow and shot it. Flew like a piece of cooked spagetti, hit 10" right from the group, almost sideways, nock left.

Cut the bare shaft back to 30.25, removed all internal weights and cut the point weight back to 145 gr. The bare shaft flies like it's on a wire and hits straight on in the group.

Do I have some kind of horrible release that requires a stiffer arrrow, or do I just not understand Stu's chart.

For what it's worth, I bought a 48# R/D Lost Creek longbow and it only likes arrows spined at 80# by Stu's chart. Went up to the trad archery shop and we wound up going WAY up the ladder on spine weight - 2219s with 145 points, 30.5 length and it shoots bullets.

Waaahhhh?
Ron

[mscampbell75]

I'm with ya!  Stu's cal. just does not work for me.  I tried it, and my bareshafts were terrible as stu called for. I was wearing out the outside of my rest.  

Bareshafted until my groups were good and then my arrows were flying like darts, with the exception of my sloppy release now and again.

Wish I had and answer for ya.  But the way I see it, If you got good arrow flight and hitting where you are looking, things are right where they need to be.  I have a touble over analyzing simple things.  

[jhg]

NEVER mind.. wrong answer.

[Bladepeek]

I probably got my modifications out of order in my post. I did replace the 170 with a 145. Better, but still too soft. Took out the insert weights. A little better. Cut 1/4" off and it REALLY straightened out. I can't see well enough to see feathers in flight, but that bright orange nock doesn't even wobble now. Changed another four arrows that still have feathers on them and I can't tell the difference between the fletched and bare shaft. The bare shaft is always in there in the cluster of arrows.

[sawtoothscream]

i stopped sing it since my results dont match. i build my first set of arrows using that and they didnt work at all. i have  a point weight kit and leave the arrows full length and try different weights until the bare shafts are good.   then i can cut them down if needed and work from there.  it seems to work for alot of people but not me

[Slasher]

calculators... charts... are generalizations.... Each bow (cut to center or not), even different strings (dacron or SBD 6 string), and the archers release will all play a part.... draw length plus arrow length will also play factors... that many variables can throw a whole bunch a things off real quick....

If your bare shafting well and your bareshafts, fletched arrows, and broadheads all hit together..... what more can you ask for? That is why bareshafting is the real test... I am a carbon guy, so I am no help with aluminum....

When in doubt check Bob Morrisons and Ol Adcock's tuning guides.... It doesn't get anybetter than being that well tuned...

[Night Wing]

Other factors that might come into play is if you're shooting with a tab or a glove where the glove has a deep groove in it caused by the bowstring. With a glove, the ridge on top of the groove causes an arrow to hop over the ridge when you release the arrow.

Just food for thought.

[German Dog]

My arrows are way weak compared to the Stu calculator.  Fun playing with the calculator but it didn't even come close for me.

[Bowmania]

I'd be surprised if Stu told you to shoot 2117's.  They sound way to stiff to me.  With a 53 lb at 30 I was shooting 2114's and 2016's.  With a 64 at 30 I was shooting 2216's and 2117's.  I'd plug that in Stu's calculator again and make sure you know how close to center your bow is cut plus the string particulars ect.

Bowmania

[Bladepeek]

Night Wing, that's food for thought. I was shooting with a deep hook and put quite a groove in the glove. I just recently switched to a less-deep, more finger pad draw and my groups have tightened quite a bit. With my light weight bows (heaviest is 50#) I don't find the shallower, finger pad draw difficult and it seems easier to get a smooth, relaxed release. Maybe that's where I need to start looking for more differences in spine weight. I may have been plucking the string.