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Alright, that is news to me. I believe you though. Now I just need to decide how much speed I need to sacrifice. I'm thinking that I want to shoot at about 300 FPS. You seemed to think that a 560 grain arrow would do that at 73#.

If I am shooting a 560 grain arrow, I would like to have the 185 grain Magnus Snuffers on there. What is the best shaft that can handle that head? I'm looking for 12%-15% FOC.
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Wow! I didn't run that on OT2 (I'm at work, lunch break) but a 560 grain arrow at 300 fps! You could shoot an armored truck with that! I did mess around with OT2 the other day, wondering about the exact same question you asked. I found that the momentum does not top out in that program. I'm not convinced that is accurate. A compound bowwill deliver a constant amount of force via the string to the arrow (at a given draw weight). According to Newton's Second Law, increasing the mass of the arrow will decrease the acceleration of the arrow, which in turn will decrease the velocity of the arrow, which will in turn decrease the momentum of the arrow. Somewhere in that relationship there must be a point of deminishing returns (this must betrue as at a high enough arrow mass, the acceleration of the arrow with the a constant force will be zero)-in other words,an arrow that will deliver the maximum amount ofmomentumas evidenced by the vertex of the parabola(the y-coordinate of the vertex of the parabola you posted earlier) as a function of the mass of the arrow (the x-coordiante of the vertex of the parabola). But I'm damned if I know how to come up with the vertex of that parabola!