RE: Tuning fixed blades ??
CBM.
Make sure your arrows spin true with fixed blades.
I have heard the same thing about fixed blades and speed.
My BK is shooting a 314gr arrow at 312fps and the muzzy 75gr heads fly like darts as of yet I have not tried the 100grers I have but will be when I get some time off work.
Will most likely use them on my 400gr arrows as thats what I will be using for hunting but even then the BK will be doing 280fps.