I am shooting a 48# bow at 28". My finished arrows are all between 515 & 525. I shot some sourwoods that are 625 grains plus. I could learn to hit what I want with them, but I question the energy they deliver. Im no math wiz my any stretch, but there has to be a threshold on arrow weight when it becomes too much. My lighter arrows penetrate my target much farther at 18 yards than my super heavies. I think Ive crossed that threshold. Kind of like too big of tires for your trucks engine. Not saying your in trouble with your rig Matty, just tossing in some findings and rough numbers of my own.