I've got a NYS Militia rifle with an unusual rear sight. It's got no elevation adjustment in the down position (no steps on the base), in the up position, it's got a small round aperture, with a larger triangular aperture above it, with a notch in it's base. The slide has no finger piece, and is held in position by a knurled clamp screw at the top of the ladder. The sight is adjustable for windage via a pivot screw near the front, with a worm and sector at the end, causing the rear of the sight to swing left and right on the base. The knob of the worm is just behind, and slightly larger than the slide clamp screw, when the sight is in the down position. Anyone have any info on this sight? Thanks,
Paul