I owned a Mark VII before I got the XIX I have now. I too used the mount that Toprudder is using and it worked out fine. However, the Mark XIX has the Picatinny rail and I could not get ANY rings to mount on it that would stay tight. I then ordered the aluminum mount that Kahr sells for the Desert Eagle. Its just two pieces of aluminum, but they get $85.00 for it! After many failures to keep the rings tight, I bought some Wiegand rings. These split vertically, and you need three hands to put them on, but they do stay tight. I tried some cheap red dot scopes first, but they would'nt last three rounds before completely coming apart. I happened to have an old Bushnell 2x scope that I had used on my Mark VII and put it on the Mark XIX. Three hundred rounds later it is still dead on. I credit the Wiegand rings. There is absolutely no loosening of these rings.