There are two elements that affect bevel width - one is geometry and whatever you say, a ratio of 4.7 against a target of nearer 3.5 is a long way off. The second element is the amount of metal behind the bevel - this is where hollow grinding comes into play. Take a look at some hollow ground razors such as Filarmonicas - the metal just above the bevel is almost a straight line. Well to a naked eye it is. That's why the bevel is tiny and yours is not.