I just swapped my scope for the williams rear peep and front globe. Currently, the peep is all the way down the ramp. The front globe is what it is. I'm still 8in high at 50 and have no room left to move. From what I read, I need to shim the front up. I'm wondering how much shim can I realistically do to the front before the gap is too much to much shim? 1/8in? 1/4in? In my mind I could need 1/4in or more shim? I shoot an older Knight Vision 50cal. 84gr by weight BH209 and a 300gr Thor. The groups are awesome, just high. I've tried lower powder charges and it's similar. Anyone ever have a similar issue? Any way to calculate how much shim can I expect to put up front or is it just trial and error? I am scratching my head, but maybe there is a simple fix I am overlooking.