CX forgiving, or I am doing something wrong

[maineac]

Ok, decided to to go to CX heritage shafts.  Used Stu's spreadsheet to figure best shaft for bow and draw weight.  I was worried about the 150's ending up to short with a 50 grain insert and 175 gr. heads.  I went with 250's (53# bow at my draw).  Started at 32" and have shortened them based on the bare shaft.  I have gotten very similar flight from 32 to 30.75".  Bare shafts group with my fletched arrows (a variety of already tuned).  Woodsmans fly perfect, though they hiss. I then borrowed an unfletched 150 from a friend at 29".  With the 50 grain and 175 tip it grouped a bit stiff.  Flying great with a 200 grain tip.  Seems odd to me that the 250's and 150's should tune so close in length with similar weight up front.  Am I doing something wrong or are these shafts very forgiving?

[MSwickard]

I do believe from my experience that the CX shafts i have used are very forgiving.  I'm using the CX Terminator Select 45/60's in my 53@28 Griffin. (my draw length is 28.5") I have these shafts loaded up w/ 100 gr brass inserts, 125 gr steel adapter, 160 gr heads.  Total arrow weight is 678 gr.  Bare shafting a FL shaft they would group with fletch but would be more nock left then the shorter bare shafts.  Best arrow flight for me had the shaft length 29-15/16" measured from groove to back of point.  This length the bare shaft would hit the target dead straight with very little nock left.

You are not doing anything wrong.  Just tune those bare shafts so they hit were you aim and have minimal nock left if you are a right hand shooter.

Mike

[Old York]

What did you enter for the "Strike Plate Position" in the DSC?

At what yardage(s) have you tested?

[maineac]

0" for strike, since the bow is center cut and my strike plate is as thin a plate as I have seen.  I have tested out to 20, which is about my max for nice group to compare.

I have it so that the shafts are straight or slightly nock right.  I went back to a full length on the 250's and they were very right of the group.

[xtrema312]

I don't find carbon forgiving unless it is a AD.  I do find some odd stuff tuning where I can shoot a longer than needed shaft with the same weight as one about right in length and have them shoot the same.  Sometimes with more weight up front on the long shaft.  All I can think of is that the higher FOC we have with carbon and a lot of extra length does something with flexing when shot that works out sometimes.  

I have to get out to 25 yd or better to really see what a high FOC shaft will due.  At short range the heavy front will just drag the shaft to the target for me, and I don't see what the shaft does in flight.  At longer range I start to see the flight better and what the shaft is doing like over correcting in flight which can give false nock direction indication when the arrow hits or move the impact point over some.  I don't shoot so much for group now after I get the arrow close.  Now I back up and see if it will fly 25-35 yd. slight nock weak and high all the way without to much nock travel weak and high or a correction swing in flight.  I had some shafts cut 31" with 100 insert and 145 point.  They shot well even with broad heads, but I would get some odd stuff sometimes.  After more work long range I saw that they tailed nock weak more and more over distance and then swung back in corrections before hitting.  I cut them down to 30 1/4" with 100 insert and 100 point.  Now they fly better yet, and they hit about the same place at short range with a bare shaft.  However, the bare shaft flies much better long range now, and this set-up is more forgiving, which equals tighter groups particularly at longer distances.  

I have a bow that is cut to center, and I can shoot one shaft size weaker than my normal arrow with about the same point weight and length.  If I am real consistent on my shooting, even with a bare shaft it shoots real well, but when I get off a little with my grip or release it really shows.  If I try the same thing in my cut out from center bow of the same weight the light spine arrow goes crazy no mater what.  Just shows me a center cut or past center cut bow can have a higher tolerance for arrow spine, but that doesn't mean it is tuned right just because it can shoot an arrow decent most of the time.

[Old York]

"0" for strike, since the bow is center cut and my strike plate is as thin a plate as I have seen."

Well perhaps there's your answer, your bow is more forgiving (cut to centre) and accepts a wider range of spines. You can look up the actual deflections of the two CE models, crunch the numbers in Stu's DSC spine converter; I believe you will find about a 20# spine difference between your 150 and 250 CE Heritage.

I'd say yay to what you have and go kill some venison   :D

[Cherokee Scout]

One problem with charts is the fact the the way the bow riser is cut has an impact on required spine. The chart may get you close but it can not account for riser cut differences.

[AdamH]

They're VERY forgiving, Im shootin CX Heritage 350's from a Roy Hall "Aztec" 56# at my draw, 200 grn. up front, fly like darts 30'' groove to BOP ... Go Figure, I think alot of it with these shafts are that they're a Carbon "Composite" and not ALL Carbon  ...

[maineac]

Thanks.  I'll keep working and try to back up some and watch the flight from longer distance as Extrema suggested.  I think I am close.