ok i've taken on board whats been suggested and i'm doing just under an inch at 12 yards and i'd say thats my max for distance.
the groups tighten up quite well as i get closer (obviously).
i think where was really going wrong was by trying to cover the target with the front optic where in fact i get better accuracy by as suggested aiming a little low allowing me to still see what i'm aiming at.
fore and rear sights are 15 inches apart and with practice my confidence has grown,time is on my side i'm off work this week
thanks for the help guys.