The Leatherwood scope mount gets an F. Jamb after jamb occured at the CQB. I took the rail off and used the iron sights, which I suck at with these eyes. In one case a jamb was so bad I had to kick the breach back to free a jambed casing. The rail is just too low. It can be raised with spacers. But to get the openning that the McCann has is at least half a centimeter, which is longer than the two screws that hold the rail to the mount.
So the McCann is back on.
So the McCann is back on.