At some point around the end of the 19th Century, scope mounts thast allowed the scope to move forward under recoil appeared. This reduces the force on the rear mount considerably and totally eliminates any possibility of the shooter contacting the scope eyepiece on firing. Even though the scope has 4 inches of eye relief this is a concern to some shooters.
For those customers who want to have a moveable scope, Leatherwood have developed a sliding mount that replaces the standard reasr block with a modified rear block and a collar that guides the scope and prevents its rotation. The rest of the scope remains the same, with the same vertical adjustment. As with all moveable scopes the scope must be repositioned to the rear after each shot.