scope issue

Does anyone know what is causing my scope to slide towards to recoil pad of the gun? You can see the shift marks where the scope was originally mounted in the attached pictures. This is the second time that these Vortex Precision Match Grade rings have done this to me. They are loctited and...

First time posting, not sure what I am looking for, maybe advice maybe confirmation of what I am thinking or maybe simple education. I purchased a new Leupold VX-6HD 4-24x52 for my new Seeking Havac PH2 in 6.5 PRC in May. I had done a lot of research prior to purchasing, talked to mfgr. reps at...