Arrow stabilization - Is spin needed?

[Stephen_D]

Any idea whether spin is required/desirable for stable arrow flight, and if so, whether a certain rpm is desirable? Or, is stable, point-on flight simply caused by the fletching drag?

(A different game entirely, but the bullet from my rifle requires about 200,000 rpm at the muzzle to remain stabilized [through the transition to subsonic] out to 1,000 yards.)

[Pat B]

You are far from subsonic with your arrows so that much spin isn't necessary. LOL The more spin your arrow has the quicker it will stablize but too much spin will reduce the arrow's speed and is noisy. There is a trade off with this as with other things. Best thing to do is find what works well for you and your bow.  I use slightly offset straight fletching on my arrows and they spin enough to straighten my arrows out. I shoot mostly wood bows these days.  For me, too much offset or helical is noisy and slows my arrows down too much. They ain't all that fast anyway. Pat

[ChuckC]

My guess....required ?  No  desireable, yes.  The feathers do two or three things.  They impart a spin if the fletch pattern is helical, and they supply a tail end drag which keeps the front end in the front,   unless of course you hit a bit cross wind.  The spin probably helps maintain straight flight with a broadhead, otherwise planing is probably going to be more prevalent.  With a field point, I wonder if there is any real difference.
ChuckC

[vermonster13]

Very important for broadheads, much less so for target points. I know target guys that bare shaft out to 60 yards to be sure their arrows are tuned perfectly if that gives you some perspective.

[Jeff Strubberg]

As others have touched on, it's not reuired, but it is very desirable.

Arrows (or bullets, for that matter) don't have to spin.  Spin gives you the same stability with less drag than other options.

Put a big wad of feather on the back and you can stabilize anything with no spin.  You will also lose performance.

[DarkeGreen]

I guess it depends on how you define required. Bullets are heavier in the back than they are the nose. They don't have to spin if you don't mind them flipping end for end of keyhole'n the target past 25 yards. They will still kill critters if you can hit them but it isn't required.  

Bows are a different matter in that they are short range weapons. Longbow are very short range weapon and the arrows you shoot are often 15% to 20% FOC or nose heavy, so it matters even less. At most peoples 10 yards limit it may not be a big deal but it does effect flight. I've played around putting feathers on arrows pretty much any way you possibly can. If your arrows don't spin you get the knuck ball effect and shooting anything but perfect arrows makes it worse. I wrapped some feathers by had on arrows to get max spin and they were pertty impressive, but I don't think that much spin is required or even desired.

I personally won't go under 3% offset for longbows but perfer a little more for compounds when I shoot them. I think 5% works good for just about everything.

[jindydiver]

I have often wondered about this but from a different angle. If your arrow spins hard enough you would have centripetal forces acting on it and it would resist curving in flight but would try to stay in the same plane as it was when shot. As the arrow is fighting to stay facing on direction and the fletching is fighting to make the arrow always point the direction of flight (in a curve) there must be a bunch of drag happening. I think you would only see this in clout shoots though, where the arc of the arrow is pronounced enough to see the effect. I don’t know much about clout setups but I wouldn’t mind betting that small straight fletchings out distance helical fletchings by a fair distance.

Has anybody been to a clout shoot and watched a helically fletched arrow being fired? I haven’t but I wonder if when the arrow starts to be obvious in its curve it gets a wobble up, from the fletching fighting the spin?
I don't have a helical jig so I can't test this myself

[DesertDude]

feathers do alot to stabilize the arrow. I found this out while bare shaft testing for the first time. I shot for years a 2117 29.5" 125 point out of my 55# @ 28" recurve. 3 white feathers, all I saw was a tight ball of feathers flying down range. I also got a perfect hole through paper. A friend says to me let's take the feathers off and see how your arrow bare shaft tests... 12" right of center @ 10 yards.  weak!!!  it took a 2219 with my set up to bare shaft test center traget at 10 yards. Conclusions. if bow and arrow are perfectly tuned then with field points you can get by with little to no fletching, but put a BH on, bad release, contact with the rest/shelf or wrong spinned arrow. then fletching is a must.
I also like alot of twist, an arrow that is flying bad also creates alot of drag.....Mark