dwaasp, I never thought about it but the BC doesn't say what letoff they achieved the speed at. If it was at 65% instead of 80%- that could be where I lost some fps I never considered.

My BC has them shooting a 300 grain arrow at 64#, that translates to 4.6875 grains per pound.
Does that mean BOWTECH voided my warranty!
I really doubt it, but its something to ponder.

Before anybody jumps on me- I Like my bow, but the 60-70#er I test shot was quicker when let down to 62# than this one is at 64#. If I'd know that was gonna be the case I'd buy the 60-70# model I test shot and back it down to 65# Instead of ordering the heavy 60.
My Mighty-mite was quicker only shooting it at 63.5# on my scale & chrony(same set up) than this one is at 65#(my scale).

NOT that I was looking for a speed demon, but IBO ratings are a major consideration when I bow shop. Otherwise I'd be shooting a tomcat.