I have a TR77 NPS (I am in australia) have done the trigger mod and put a DIANA 4x16 42mm scope on it, put around 500 shots through it and most of the time it shoots <2cm groups (standing) at approx 30m with clipper diablo extra heavy pellets (by far the best so far tho I have some JSB exacts coming) but I am having a lot of trouble with having to re-zero the scope after 30 or so shots, the scope was moving quite badly and I have made a temporary fix of putting a pin in the hole with mounts butted up to it while I wait for my one piece stopper mount to arrive. I am wondering if it is the scope not handling the fierce recoil of this rifle and are there stronger ones available.