Thanks for all the input everyone, I went to the indoor range last night and put my original mounts back on and shimmed the rear one, not ideal, but I need to stop fiddling and start shooting

I have been looking in chairgun and am currently exploring the potential of BKL stuff (one of you posted a link to a dovetail droop compensator), chairgun and that bit of kit correspond nicely at 0.007". Only thing putting me off is cost and availability (add the cost of the mounts to the compensator)

Another thing I noticed about the B Square, the bottom half of the mount is able to rock from side to side, I guess because of the thread tolerance and I dont see how this movement will stop even when the caps are on and all is secure. When I have a little more time I'll put your suggestions to the test.

Many thanks

Barry