I was working our range's sight in days at the end of Sept when a guy shows up with a modified Mosin rifle set up like a scout type. He had a scope where the Mosin's rear sight goes, black polymer stock, cut down barrel.
I shot three rounds at it at 300 and had no problem quickly hitting the gong 3 out of 3 times.
Now I'm a purest when it comes to vintage military rifles. I like to keep them "as issued" per the CMP Rules. I like the idea a scope on them if I don't have to modify the rifle. This mount does that. You push our the pen that holds the rear sight on and install the mount using the pin holes on the sight base. The mount has a couple of set screws that lock down the mount to keep it from teetering. Makes it pretty solid.
I ordered one and installed/bore sighted it last night, I zero it when it gets daylight.
Here is the set up on my Mosin:
The whole system, mount, scope (AIM 2X7), plus a add on but plate (which uses the existing but screws, again without modifying the gun) plus a new sling.
I kept the sling that came with the rifle. The butt pad is suppose to soak up a lot of recoil but I don't find the recoil objectionable so I didn't install it.
The Sportsman's Guide sells the whole kit for $60. Not bad, keeping the rifle set up cheap (I paid $99 for the rifle). Should be fun to play with. If the cheap scope doesn't work out it would be nothing to replace it.
Here is the link to the Sportsman's Guide showing the Mosin Scout Set Up.
The Sportsman's Guide - Hunting & Outdoor Gear, Shooting Supplies, Military Surplus, Survival Gear and More!
Just thought I'd pass it on to those who want to add a scope without screwing up the gun.