Buy a gun. There's a reason why every seasoned scout has one. They do this for a living and they don't trust there "eye". Throw in dad bias and it's always wrong and always to the high side. I've seen dozens of dads say their kid throws higher than they do, in fact every single one. I've never seen a dad say his kid throws lower that what the gun will tell them later. End the debate in one swipe of the credit card. Buy a gun.