I've been reading several posts on arrow spine and it's left me confused. What are the problems with an under spined arrow?
What are the problems with an over spined arrow (I've only heard of being underspined, I assume because everyone wants a lighter arrow)?
And the charts are just a starting point right?

I was shooting GTpro hunters 7595's Hardwoods (spine is 300) and they shoot fine, quiet, and accurate (with vanes or feathers).

I just bought some ST AXIS 400's (spine is 400) and they shoot well but the arrows I put feathers on make noise. My thought is they are probably a little underspined and the noise is caused by the feathers working (over working).

Your thoughts?

Thanks

I guess I should have included my particulars.

2005 Bowtech Defender 70#, 29 1/2" Draw, arrows are cut to 27inches and fletched over eze crest wraps. I use 100 grain heads and my favorite color is green.

you have to figure out proper spine for your given setup

with your setup you SHOULD be ok with a 400 spine..

feathers tend to make noise..period. i shot them and they always had a little sound to them. i didnt like it. that and they got ruffled and looked bad and i could never get them right again...i switched to blazer vanes. some broadheads also make noise...

spine is very important though..if your spine isnt right youll have a heck of a time getting broadheads to fly right. my bow grouped fieldpoints great...but once i put BHs on i had major issues. theres a whole topic of weak and stiff spines and its effects...my spine was too light for my setup. luckily if i trimmed 2 inches from my shafts it would fall into the proper range..and that worked wonders...

if you have broadhead problems you could back off the draw weight..that will put you more into the 400 range..but you should be in it now with that setup..