Jackson's has a f.o.c. calculator.1st thing you must find out is if you are within specs..If you are,and the f.o.c. isn't too light then it's most likely another tuning problem.Your CX terminators weigh approximately 495 gr with a 125gr tip.The f.o.c. on that arrow is 9.5%.That's good..First of all you really don't need that long of an arrow.The arrow should be cut so that 1" of it is past the rest(not including tip).The aluminums you are shooting weigh approx. 564 gr!The f.o.c. for that combo is 8.7%...a hair low,but still acceptable.Aluminums are always going to be heavy.If you want to go with light I suggest the CX maxima's.That's what I'm using.If you want some around the 6gr per pound range go with the Easton Axis.They are both very high quality arrows.I would double check my bow for tuning problems.Since your f.o.c. is not a problem.Also I would go with a shorter arrow.Hope I helped.Let me know if you have anymore questions.

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