Accuracy Questions

[konrad]

Questions:

1. In the never ending quest for the ultimate in long range archery accuracy, all other things being equal, which is more critical, arrow straightness or uniformity of weight?

It would seem to me that varying weights would produce vertical “stringing” on the target (related to time-of-flight/velocity variations) while shafts with straightness issues (say .006” total indicated run out) would produce more rounded groupings.

2. On any given bow draw weight/draw length, will shafts of a slightly stiffer spine produce better groups than shafts of a slightly weaker spine or will the opposite be true?

Of course, answers submitted will require apt justification for given opinions!

[lokidog]

Personally, I think you are correct with #1, but I am not sure how out of straight it would have to be to throw a wider group.  Seems like inconsistent grip would cause as much or more variation.

#2 is another issue.  I get decently tight groups with arrows that the computers say are not stiff enough, but they are in a different spot than the arrows with the recommended stiffness.

 

[JJD]

Define, "long range archery"?

[JPhelps]

I have read some articles stating "consistent spine" will yield the best accuracy

[xsf1]

I like to shoot my arrows before I fletch them, first I will mark them on the nocks of course and then shoot at 20 yards for a few rounds. If I have a consistant "flyer" then i will label that as a grouse or rabbit arrow and practice throughout the summer with it. thats the variance of shooting normal hunting arrows rather than target arrows. As for your second question it seems that a little stiffer wouldnt hurt your groups, it would definatly hurt the FPS so your arrow would drop more but increase the momentum. that is if you are looking for penetration. I do now that the olympic archers use arrows that are as light as they can be with the smallest diameter to reduce on crosswind variance. I could be wrong though...

here is a couple articals that are interesting

http://tradgang.com/ashby/Momentum%20Kinetic%20Energy%20and%20Arrow%20Penetration.htm
http://www.archery.org/UserFiles/Document/FITA%20website/05%20Rules/01%20C&R%20Book/Book_2012/EN-Book4.pdf

some software that you might want

http://www.pinwheelsoftware.com/

[Matt]

Not sure how far that you are talking about and/or field point vs broadheads.  I shoot a lot of competitions with shots over 80 yards and out to 102 yards.  I will just address field points because everything is crucial with broadheads at all distances.

  Your arrows have to be spined perfect for your bow set up.  Throw out the charts they are just a good place to start.  Some arrows are chosen with slightly weaker spine but react great out of the bow.  Slightly stiffer is better because the arrow recovers faster.  Case in point I have gone through 3 dozen arrows so far this year to get the group I want at 100 yards.  Once I found the right spine I then played with lengths to reduce the size of the group.  FOC is also very important for accurace, you need enough point weight to steer the arrow down range.  A lighter arrow will lose speed faster than a heavier one.  And of course if you are going to shoot long distance then you will want a shaft that is .001 straightness.

  Now for the bow.  First draw length must be perfect and comfortable because after 60 yards your anchor point will start to change so that you can center your sight in your peep.  I like to set my peep hieght at 40 yards for optimum comfort.  Then your center shot must be exact.  A 1/16' of an inch off at the tip of the arrow on the rest equates to 8" off at 100 yards.  Stabilization is also important.  You need to have enough weight out front of the bow so that you can hold steady.