Thanks again for all suggestions, tried again this morning to compare two different seating depts., the first target shot was using my usual depth of .135" and the second target was with the depth set at .155". No other changes were made to the usual load of 63 gr of Wano PP.
On the first target four shots went into .580" and one flyer made the group .870", I was more than happy with that. 
For the second target I extended the seating depth to .155", this is about as far as my seating tool will go. This target measured 1.190" with the best four going into .975". Conditions were excellent with a light 5mph breeze that was variable from 3 o'clock to 12 o'clock. My cleaning routine was one damp patch used both sides followed by one dry patch, again both sides. I will try Boats suggestion of cleaning more thoroughly between shots next time. 
As a matter of interest I do have about half a kilo of Swiss 1 1/2 FG that I could try as well. Previous experiments with the Swiss have shown that, load for load, it delivers more velocity, whether I need more velocity or not is a moot point.
Thanks again for the educational input.
Mike.