SJC Glock C-more Mount

Installation Instructions

Contact S & J Customs before starting if you do not understand any of the following instructions:

  1. It is your responsibility to make sure your pistol is unloaded and safe before starting.

  2. We recommend this mount only for installation on 9mm Glocks with standard size receivers

  3. We recommend that the ejection port on your slide be lowered to allow additional brass ejection clearance.

  4. Knowledge and ability to properly adjust brass ejection angle is required for consistent functioning of the pistol with this mount attached.  After test firing, examine the mount for indication of brass hitting the ejection port, the bottom of the mount or both. Then modify the impact point of the ejection post on the shell casing to modify the ejection angle.  Recoil spring weights and extraction system angle and tension may also be required.  Properly adjusted ejection angles will produce a consistent arc of cases easily seen if standing close to a walled surface when firing.

  5. Remove the iron sights both rear and front from your slide.

  6. Remove the slide assembly and trigger pin from your pistol

  7. Place the mount on the receiver aligning the rear hole over the trigger pin hole

  8. Insert the supplied trigger pin screw from the left side and tighten lightly

  9. Re-install the slide onto the receiver under the mount

  10. Install the C-more attachment screws through the mount and lightly tighten against the top of the slide.  By loosening and tightening the C-more screws one will be able to lock the mount in the desired position parallel to the slide or at a slight angle if desired.

  11. Mark positions and then drill pilot holes through the front holes on the mount.  Holes should be drilled from both sides. Do not attempt to drill all the way through from one side. Do keep the drill bit perpendicular to the surfaces on the mount.

  12. Remove the slide and mount from the receiver

  13. Drill out the pilot holes with the proper bit to allow installation of the supplied bushing shafts into the receiver.  We use a 19/64” bit.

  14.  You now need to inlet the sides of the guide rod/spring trough in the frame to accept the bushing flange and prevent any interference with the function of the recoil spring. Proper inletting will place the outer most portion of the bushing's barrel no more than flush with the outside of the frame. Note that the bushing flange outer diameter has flat sides. The inletting process needs to closely match these flats so the bushing will not spin on tightening and loosening of the screws. We use an end mill to bring all of the inletting elements together in a single operation but using a dremel tool carefully will be fine.

  15. Install the mount aligning with the bushings and trigger pin hole.  Install the supplied screws being careful to not over tighten.  Use low strength loctite or like product to prevent loosening of screws during firing.