I wanted to do cast bullet hand load development for an 03 Springfield rifle at ranges of 100 and 200 yards.
My eyesight has made using even the best iron sights at longer ranges rather less accurate than 40 years ago... So I wanted a scope on the rifle, but didn't want to alter it permanently. The B-Square mount did allow this.
You must remove the magazine cutoff to install the mount, and while mount is installed, it prevents removal of the bolt for cleaning.
So if you've got a rod cleaning system, either you must lose zero if you wish to clean from the breech, or clean from the muzzle with the danger of wear to the muzzle from the rod.
Or you can buy a "pull through" cleaning system... (which I did- I highly recommend the Otis military surplus AWCS kits! Great values at around $40.00 plus shipping on eBay occasionaly if you look around).
It took a bit of fiddling to get the mount on and adjusted close enough to parallel with the bore to allow bore sighting. Once that was done, I found a very tall cheekpiece necessary to use the scope properly- Which can be faked up from scraps of rubber foam and the non adhesive surgical wrap.
The mount is Aluminum, and will come loose under recoil from military 30-06 or other high velocity jacketed bullet ammo after a while unless you use locktite and considerable care in your installation. After re-installing the mount, I proceeded to test handloads with cast bullets at moderate velocities- The mount held up well using...