Thank you for your reply - and a very happy New Year to all.
You are right to say that I should let the target speak.
However, the aperture appears to work as a clarifier for the leaf sighs and front sight bead rather than as a sight in its own right.
The 200m leaf does not fold flat, so it is the position of the foresight that determines the point of impact, not the aperture, whose functions are thus to allow one to see both sights simultaneously and to align the eye rapidly with them.
With the aperture all the way over to the right, as it is, I don't get the benefit of the latter function, since, on mounting the rifle, I find myself looking at the right "ear" of the forward scope base, not through the "V" of the rear sight. No doubt my being left-handed contributes to this.
Moreover, the resulting need to look askance through the aperture to see the front sight bead in the rear sight "V" casts a shadow over my view of the sights.
This is why I have been looking to adjust the aperture before heading out to shoot the rifle.
