I am currently shooting a Carbon Rebel arrow from what the pro shop guy said they are CX arrows. They are 45-60, and from what i remember they are like 11 gpi. Ok i want to get some new arrows that are not quite as heavy and smaller o.d.

Well i went to CX site and if I follow there selection chart it says to go with a 60-75 in the arrows i want which are the terminator selects, but at Keystone where i was gonna order the arrows there book says the 45-60 is what I need. Well it seems that the 45-60 I shoot now is fine. Am I missing something here? I am shooting a 28" arrow at 70 lb draw weight. I want the 45-60 because it weighs only 9.5 gpi, but dont want to be under spined..

Im all confused...
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