Lever Action Scope Mount - Detailed Installation Instructions
1) Pre-fit the mount by loosely installing the four mounting screws. The two longer screws will be installed at the middle of the mount in the forward holes of the receiver, and the two shorter screws will be installed at the rear of the mount in the rear holes of the receiver.
2) To check for proper fit, tighten one mounting screw to ensure that the screw clamps the mount to the receiver while allowing for proper function of the firearm. Loosen that screw and repeat these steps for each screw. If the bolt is locked in position or drags on a screw, ensure that the screws are in the correct location (see step #1). If the screws are in the correct locations, it may be necessary to slightly shorten one or more screws to provide bolt clearance after installation.
3) After pre-fitting, remove the mounting screws and apply a threadlocker to the threads of each screw. We recommend Loctite® Threadlocker Red 271 or Permatex® Medium Strength Threadlocker BLUE. Reinstall the screws and tighten to the desired torque. The preferred method for tightening the screws is to use a torque wrench, such as the Wheeler FAT Wrench®, and tighten the screws to the torque specified for an 8-40 fastener (28 to 30in-lbs).
Tip: Nail polish or blood will work as a field-expedient threadlocker.
4) Apply threadlocker to the threads of the brass-tip stop (set) screw and install the screw in the threaded hole at the forward end of the mount. The length of the brass tip can be shortened.
5) Insert a small piece of printer or notebook paper between the brass tip and the barrel and rotate the stop screw toward the barrel until the paper drags when removing it. This will leave a gap of approximately .003in between the brass tip and the barrel.
6) Apply high-pressure grease or anti-seize to the dovetail contact surfaces of the rings and mount, and then install each ring by inserting the dovetail base into the mount and rotating the ring 90º relative to the mount. We recommend that you choose a direction of rotation for installation, and then reverse that direction when removing the rings. For example, rotate the rings clockwise during installation and counterclockwise during removal. We also recommend marking the bottom of rings to indicate the mount position and forward direction (F→ and R→), which will allow you to always install the rings in the same position and direction.
7) We STRONGLY recommend that you align the rings using an alignment tool, such as those offered by Wheeler® Engineering. We also strongly recommend that the rings be lapped prior to installing a scope.
Tip: To prevent deflection of the mount during lapping, run the stop screw down until it JUST BARELY touches the barrel. After lapping, back out the stop screw to adjust for proper barrel clearance (see step #5).
8) Install a scope, and then check the clearance between the brass tip and the barrel. If there is any change to the clearance, this indicates that the scope is in a bind and causing deflection of the mount. Confirm that the rings are aligned and lap the rings again, if necessary.
Tip: If the mount deflects upon scope installation even after you have lapped the rings twice, it is likely that your scope is not perfectly straight, which is not unusual. In this situation, we recommend that you remove the scope and adjust the stop screw to provide for approximately .003-.006in clearance after the scope is reinstalled. The amount of clearance does not have to be perfect, but there must be some clearance, so that the brass tip is not touching the barrel at rest. Note: The forward end of the scope/mount assembly can be deflected by hand to cause the stop screw to contact the barrel but will rebound when released.