My son shoots an Oneida Areo Force set at 71 pounds. His arrows are XX78 2512's, 29 1/2" with 125 grain heads. He is thinking about changing from 3 5" vanes to 4 vanes. What would he gain doing so? Should he go to a 4" or 3" vane? Straight fletch or right helical? Oh yeah, he is a release shooter. Looking for pro and con opinions on this. Lawdog

I use 3" using a straight jig and 1/2 deg. arch.
I have found this set up to work with all size vanes or fletching's for hunting. Target shooter's use smaller vanes but also tend to use smaller shafts.
Using 4 vanes will add wieght to the shaft and have more problems with clearing the rest when launched. If you are having problems with arrow flight I would recomend paper tuning.

gsp,
I beg to differ with you on the adding weight thought, as I shoot 4 - 4" vanes as opposed to 3 - 5" vanes and if care is taken when gluing on the vanes,(no excess fletch-tite) they weight the same. (weight of 2 arrows I built) I shoot 4 fletch so I don't have to worry about the cock vane and can "reload" without taking time to feel around or look at the arrow while keeping my eye on the target which is a must when still hunting.

As for going down to 3" vanes I have never been able to get consistant broadhead flight with the 3" fletching. I shoot an older Onieda Eagle at 62# shooting 30 1/2" 2413's tipped with 130 grain Muzzy broadheads.

Just my 2 cents based on my spending time shooting a number of different combinations including carbons.

Good Luck!

There are two issues here. One is arrow stability and the other is F.O.C (Forward of Center).

Stability:
I would not use anything less than a 4" fletch for shooting broadheads, and a 5" would be even better. A fieldpoint will fly just fine with just a little guidance from a 3" fletch. A broadhead however is a different animal. Broadheads have a tendency to try to steer the arrow. The bigger fletches have the ability to counteract that steering affect and stabilize the arrow. I would also add at least a 4 degree helical to the fletch. (left or right is just personal preference)

F.O.C.
F.O.C. represents in percentage how far forward of the center of the arrow that perfect balance is achieved. When you change the weight of any component on an arrow you change the balance of the arrow itself. This directly affects the arrows flight. The bigger the change in weight, the bigger the affect on arrow flight. Going from a 3.5" to 4" vane will not make a huge difference in flight. In looking at the components you mentioned, your arrow weight should be around 540 grains. F.O.C. with 3.5" vanes is around 10.7 and 4" should be around 10.6. Ideally you would like to move that F.O.C. a little higher for broadheads. Say 12%-14%. You can achieve this by either using a heavier head or taking some weight off the back end by either switching nocks or going to feather fletching. Simply by going to a 5" feather you would gain more control to stabilize your broadhead and set your F.O.C to 12.4%.

I have inserted a link to some good information on this subject. Happy Shooting
Fletch Length

I should have mentioned I use this set up with machanical broadheads and have never had bad arrow flight with 3" vanes. I also switch and shoot the same arrows in 3d with field points.
In my 15 yrs + shooting I havent seen to many shooters (3d or hunting) with 4 vanes.
What works for one doesnt always work for others.
With a properly tuned bow, a arrow should fly straight with out fletchings. wieght will have to be added of course,to the tail end of the shaft.

[ 03-25-2003, 23:22: Message edited by: gsp ]