tying out some beeman mfx 400's for me longbow,although they seem to be spined correctly,they are making a harmonic noise as they fly. I like the shafts,they are much noisier rattling around in the quiver than other carbons.They almost sound like aluminum bare shafts.The shafts are full length.Is there a certain length ,point combination that is going to make that harmonic noise as the arrow is in flight?
Cut them appropriate length for your draw and tighten the heads up(add a little lock tite to the threads)use feathers not vanes.Check the inserts are installed corectlly.And check to make sure they are spined right.Seaming to be spined correctly and spined correctly are totally different.you can also change head weight (up and down) till they fly perfect.If that doesn't fix it shoot wood!
I would say they are spined correctly,I shot 4 bare and 4 with feathers and grouped them together all afternoon.They are a little long for my 28" draw,but really don't want to cut since they are flying so good.Might take your advice and cut off a little bit and go up in point weight if need be. thanks
Make sure the points are tight.That may be the number one source of noise.Put some bow string wax on the threads and see if that helps.
Definately check the points.
If your points back out, rub a little string wax on the threads. This won't get hard and it keeps the points from unscrewing. If you still have noise,check your fletch for weak spots or nicks. A weak spot in the fletch will fold over in fight and make a humming or hissing sound.