I have a Leupold Vari-X III 3.5-10x40 Long Range scope on an ARMS #18 with ARMS #22 Low rings. I have about 3/8" clearance above the handguard, and just a peak of daylight above the rear sight. Your 50mm objective will probably have no problem up front. Any extra room needed in the rear can be had by cranking the rear sight down, but then of course you'll loose your irons. Send me your email address and I'll send photos of my setup.