there is a chart Funny thing is a s300 equals 5.8 FCM ok So at first I though simple its between a project x 5.5 and 6.0 but thats not the case. a project x 5.0 = 5.5 FCM and a 5.5 =6.0 fcm and a 6.0 = 6.5 fcm and 6.5 = 7.0 confused yet? i got this chart off of Golfwrx.com for example Ive had project x 6.0 and the new g95 6.0 both flighted and both were more firm than the s300 I had a 5.0 once and it felt more like a r 300 which is 4.8 but as i mentioned a 5.0 pro x is actually 5.5 so in pro x if you get a 5.0 its just a little less firm than a s300 and a 5.5 is a little more firm than the s 300 for example like I said i hit the pro x 6.0 i need a little more stiff so i tried a 6.5 i didnt like it no feel and granted it was on a wedge. So i tried a dynamic gold x100 perfecr its a 6.8 fcm the so rule of thumb if you know what project x is 5.5 is 6.0 and s 300 is 5.8 its really not as confusing if you look at the chart look it up on golfwrx.com and download it it helps and dont even look at kbs its a night mare
