question about building out arrow shelf

[Lone Ranger]

trying to tune some 55-60# surewood's to my 41#'s at 29" Kodiak Hunter and have some questions.

I am using OL Adcock's planing method here:  http://bowmaker.net/tuning.htm


I fletched up 3 - 31.5" shafts with 125gr points and 3 matching shafts sans feathers and have been shooting groups- they are slightly weak- I have the knocking point ok, and am braced around 7.5" (that may move slightly) I added a 1/16th piece of balsa scrap to the arrow plate and that helped LOTS. now, should I remove that and cut 1/2 an inch to all 6 shafts and see where that gets me or leave that spacer in there?


thanks,
L.R.

[snag]

What are the length of the fletched arrows in bop? You said the Hunter is 41#@29". Is 29" your draw length? I'm thinking that these 55#-60#'s are slightly stiff with 125gr tips unless you can get them down to 30 1/2" bop. Then they should fly good. That's if your draw length is 29" and you want to stay with the 125gr tips.

[wtpops]

if the build out worked then leave it and have fun. If for some reason you dont want it in there then remove it and cut the shafts but i would not cut more than 1/4" at a time and only one or two shafts at a time untill you get them just right then cut the rest to length

[Lone Ranger]

if BOP mean Base of Point then yes, bop is 31.5"

yes, my draw length is 29".

the non fletched shafts are grouping to the right of the fletched shafts which make them weak, not stiff.

opinions?


L.R.

[Bjorn]

Each 1/16 of sidewall equals about 5# of arrow spine. So you could either build out 1/16, or cut 1/4" at a time. I would tune more with bareshafts because they will tell you the truth about what is going on.

[Lone Ranger]

Bjorn that is the info I wanted. couldn't find it anywhere! I think I am gonna pull that 1/16th shim out and cut them. when I doubled the 1/16th shim I got HORRIBLE flight. a 1/4" cut doesnt seem like very much to me though? I certainly don't want to cut too much. I wish my accuracy was better I could do this whole tuning process so much quicker and with less shafts!

I guess I should ask how much spine cutting 1/4" or 1/2" of arrow shaft adds to the arrows?


L.R.

[Bjorn]

1/2" of shaft equals about 5#. Once it is cut it is hard to put it back-go slow.

[Lone Ranger]

cut 3 times and am at 30.75 seems to be pretty freakin close right there.

it was soo blazing hot out and I had shot so much my form was suffering, but when I knew I had good shots they were really good. the bare shafts were just a hair to the right (weak) and they were on the same plane (verticly)

I think I am done. Time to fletch the rest!
thanks so much for the help!

L.R.

[SCATTERSHOT]

I think you're done. The fletching will stiffen the shaft just a hair, too, so the end result should be right where you want it.