The only problem is I'd still really like to keep it adjustable. I tried replacing the little spring in the stock, but the orange plate on the inside was warping and looked like it would snap to easily. And I just can't bring myself to drill or do anything to my precious lil longshot...
That last paragraph was well stated, bpso86...I'm not sure I would have been as civil. No offense Jergling, but that post didn't make much sense at all.
As for your orinal equation, bpso86, what are each of the variables there? That is, whats r, h, o, and P?