I'm building up a vintage Rapid and did not want a bulky or non factory look. So I picked up some CCOP 34mm rings and removed the picitinny portion of them and machined them for the Rapid style that is all its own. I've seen someone in the EU selling 30mm rings and gave me the idea to make these fit. They turned out pretty sweet. Maybe a little tall but if I build a shrouded barrel I needed a little more clearance.