We will need a bit more info to help you. Like the bow make, model, AMO length, etc. We also need to know what kind of string you got. How many strands, what string material, what length, construction, etc. 6.5" is low for most recurves, but there are some that use a brace that low. Best is to check with the bowyer and see what the recommended brace range is for your bow and use that as the guideline.