Hi Viz.
Sounds like you are either canting the rifle, or the reticule stadia isnt level to the rifles scope rail, proberbly the latter.
Get the rifle fixed and level on a bench or table, loosen the mount rings until you can just rotate the scope.
Put up a plumb line about 10 yads away, and looking through the scope, line up the ret stadia with the plumb line, and then gently tighten up your mount rings again.
Nice rifle by the way.
Hope it helps to solve your problem.
Bill.