Mount a red dot scope to your MR1.
The MR1 model is notorious for having very little room on the upper receiver for scope mounting. The mounting system requires that the rail be 13 mm in length with a 3/8-inch dovetail. Most mounting systems require at least 20 mm of rail length. As of late 2010, RAP4 was the only mount functional for the MR1.
1. Attach the RAP4 mount to the rail. Align the rail with the opening in the bottom of the mount and slide the mount onto the rail.
2. Tighten the mounting screws located on either side of the mount and discern whether an offset is needed.
3. Offset the sight clamps to the right or left, if your carbon dioxide tank is located over the center of the gun, by inserting the small black spacers into the spacing ports. Again, tighten the ports using the screw on the side of the port.
4. Insert, after the mounting system is installed, your red dot optic of choice into the clamps and close them. The sight will be secure and also ready for immediate replacement, if necessary.