I'm replacing the old scope on my 7mmRM and the new glass is a 30mm tube. The old scope was a 1" Vari-X 2 Leupy in a dovetail front and a windage adjustable rear (not sure who made the base, probably Redfield) I'm not really sure which way to go with rings and bases. This is a BDL with a sporter contour. I don't want to put a rail on it.