Bobco is right. With the GT shafts you can buy inserts to adjust the weight of the shafts.
http://www.goldtip.com/products/fami...&rnd=129201952

It's one option but you're bow will produce the same ke with a slightly lighter shaft as it will with the heavier shaft.

I shoot the 7595 Gt Advantage prohunters and I'm shooting 74lbs. The arrows react well off my bow but if you're only shooting 60lbs I think you'd be in for a tuning nightmare if you bought the 7595 shafts.