Guess each is an individual but I can shoot 27" Beman ICS 500's up to 63 lbs. My draw is 27 1/2". That's the highest I've shot them. I can also shoot ACC 3-18's up to about 60lbs and I think the spine on them is .560". I used to shoot 400's but found I gained an incredible 20fps going to the 500's. I never thought it would be that much, but the chrono doesn't lie.