For what, your average deer or a rhino? I can't think of a modern bow out right now with any arrow that would spine right for it that would not have enough KE to effectively harvest a deer. Especially if you have a normal draw length and draw at least 50 lbs of peak draw weight.

That 300-305 fps, is that what the bow is rated at for IBO specs, or what you are actually shooting with your set up?

As far what KE you would have we would need to know more info, like how long the arrows are, what sort of fletchings they have, tip weight (or the total weight of your finished arrows) and the exact speed YOUR set up shoots them.

Paul