When I competed with roundball muzzleloaders from '84 to about 2003 the NMLRA called "notch and post" sights "open sights" (presumably because the rear notch sight is open at the top and there is no hood over the front sight) and aperture sights were not included in that classification. There is a definite advantage with aperture sights over notch and post, and usually one could not compete against the other. Both aperture, and notch and post, fell under the category "iron sights". I understand what you mean however, no problem.
There were two brands of target .22s we had at the range at camp. One was a Mossberg and I cannot remember what the other was. I fell in love with competitive shooting there.
