Why 10 meter precision shooters us diopters vs Scopes ?

 I finally had a little time to try the 10M challenge today. After setting everything up and trying to line up the target i realized that I couldn't even pick up the outer ring well enough to aim with my diopter sights. I really wanted to do this in real 10M fashion but I guess I'll have to admit my age and try something else.

The AGN 10m target was designed for scopes not for diopter sights. You need the official 10m target. It has the black spot with white scoring lines.