RWTF,
xausa is correct that the screws are not set screws,but some only go half their diameter into the rail, instead of the full diameter.For both types,it's pretty "iffy" to drill the holes. I recommend you don't try it if you can avoid it,by adjusting the focus and learning to shoot it with your head at whatever position it takes to see through the scope. If you insist(after all,it will be your gun), be advised you will have to drill the rail through the base because the rail is tapered and the base helps keep the drill from "running".Also, the Germans use a small cutter,similar to an end mill, in a breast drill to cut a "square" seat for the drill to start in. There should be a "center" on the underside aligned with the drill,to keep the hole lined up.The drill should be about the minor diameter of the screw, so you don't wipe out the threads if you drill too far.Then you would have to run a tap through if the hole is full diameter. This is a lot of "scary" work to move the scope a fraction of an inch. Good luck.
Mike
