hey guys I got a Nikon buckmasters 6-18x40mm w/ target knobs sitting on savage 17hmr. I use it for picking of pest. But I would like ot take longer shots. Right now I just been using hold overs. But I would like to be a little more precise. Does anyone know how repeatable these scopes are? I sure dont want to get out there and start craking and miss comepletey.