ORIGINAL: OHbowhntr

You're measuring KE now, not momentum, which is really ok for the most part if you are trying to achieve max KE, because max KE should have you carrying plenty of momentum to do the job on anything in NA. And unless you're planning on a trip to Africa, you'll be fine with just about whatever you place on that string, as long as it's above the recommended IBO weight. I think based of of some number crunching, it looks like around 500 ought to be hitting max KE based on some basic guestimates of your set-up, and if you were to drop weight to 65#, you max KE should be around 490, using "The Archery Hut Calculator," which I'll trust more than OT2 at this point. Question is what is the IBO on the Birth Certificate??? I used 340, as they always seem to come in low, and my numbers were hitting pretty close to what you posted. This calculator ( http://thearcheryhut.com/calculators.php ) is pretty close from everything I've used it on, and I'll go as far to say I trust it more than the OT2, which basically makes my purchase a waste of $25, but so goes life.