Thanks arthur I was also wondering about carbons, thats what I shoot in my compound. You talk about getting weaker or stiffer spines and thats what I meant by I dont understand them. What is stiffer, a higher number or lower number? the chart I looked at suggested 2314,2215,2216,2117 shafts. Whats the difference? You guys suggest a 2016. I' ll have to take your word for it because these numbers really make no sense to me. The carbons I shoot are in bow weight brackets and weight per inch. With them its easy you just get the right weight group and make sure your total arrow is heavy enough for what you are doing.