I recently acquired a very nice 1956 M_S in 7X57. It has the Lyman #36 sight on the bolt release. The little flap with the smaller aperture is there, but I'm not sure if it's operating correctly. If I want to use the larger aperture, the smaller aperture only swings 90 degrees, ending up parallel to the line of sight. That's fine as far as seeing and shooting go, but when I cycle the bolt it bumps that piece and moves it back, obstructing the view. It was easy to inadvertently move it into the wrong position in the woods as well.

There appears to be a recess for it to swing into when not in use. The piece would have to swing almost 180 degrees to fit into that recess, but as I said, it only swings 90 degrees.

I'd appreciate it if someone with one of those sights could check the swing of that small aperture. I suppose I could just remove the screw that holds it and avoid the problem. The larger aperture just works better for me in the woods.

I had one on a nice little M/S 6.5x54 carbine some years ago, the rear ring is split so the bolt has to move the arm back and to the left out of the way as the bolt comes back through the rear ring and it closes when you close the bolt on the round, so it has to make a 90 back and then another 90 on return to lockup if its working properly...mine worked quite well and it held its zero. I am pretty sure it was a Lyman. I not real clear on the problem without seeing it, but from your post if you can remove the small apature, then do it, its of little use IMO, the large one is for hunting and its good enough for target..Be sure and save the small one for originality however..

Thanks, Ray. I ended up removing the small aperture. It's stored away with the barrel-mounted rear sight that was in the way when I looked through the peep.