That did it, thanks all

Hove.
I've just slightly straightened the coiled wire spring, that'll put more pressure on the back of the top sear, I'll leave it an hour, see if it settles and sticks or does what it should.

the final sear doesnt always move, leaving gun still cocked despite all other sears actioning. An energetic flick of the trigger shocks it into releasing. I have trigger plate off, sear moves ok, I can cock and fire at will, but if I leave it an hour, the big sear sticks. I've given it a quick polis...