An interesting look at Foot Pounds of Energy here. I decided just out of curiosity to calculate this to see what it looked like. As a side note, let there be no doubt that 60fpe with a Slicktrick will kill any animal under 2000lbs without any problem at all.
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330 grain arrow with 100 grain point 280fps 57fpe
355 grain arrow with 125 grain point 270fps 57fpe
375 grain arrow with 100 grain point 266fps 58.9fpe
400 grain arrow with 125 grain point 260fps 60fpe
417 grain arrow with 125 grain point 254fps 59.7fpe
450 grain arrow with 125 grain point 244fps 59.5fpe
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It would appear that the 400 grain weight is the best combination for Energy with this bows draw weight and cam curve.

Also funny to me that it's the combination that shoots so well and has been the primary combination used for well over 100 big game animals( hunting and culling). Guess I should not have been surprised by what I already knew from experience, but it was a little surprise to see this work out with the math formula's as well.

www.huntingadventures.net
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