Wow, you must be using some light shafts ? My total weight is 425 gr. with the 100 gr. Shockwaves and I'm getting 338 fps. My bow is factory rated at 370 fps but that's with 370 gr. bolts.
Do you have heavy inserts in them? I don't, hence the heavier broadhead weight.
These, but with 150's
ARROWS
