I was always told; the closer your line of sight is to your barrel, the better. Can anybody tell me at what point you are compromising this theory by using a 50mm objective lens over a smaller objective lens? Is distance you are shooting a determining factor? Is versatility reduced by a larger scope. Is there a happy medium or is this whole idea flawed? If not, is it unadvisable to shim mounts to attain the closest possible distance from scope to barrel?