Sig Cross | APS OEM CHEEK RISER INSTALLATION GUIDE

The following is a installation guide for professional gunsmiths. Any personal attempt is at your own risk.

!SAFETY! Ensure the firearm is clear of attached magazines and ammunition from the chamber before proceeding further!

 

Disassembly (OEM Cheek riser)

    1. Unlock and loosen clamp lever.
    2. With a narrow tool, compress a cheek riser pillar spring away from the retaining pin until it falls out free. Repeat for the second pillar spring.
    3. Remove cheek riser from the OEM stock.
    4. Remove clamping lever arm, pay special note to the order of assembled hardware components. From left hand side to right. Nut, stock body, plastic spacer, stock body, washer, lever arm, bolt. 

Assembly (OEM Cheek riser)

    1.  Repeat step 4 in reverse, be sure to install the steel washer, use without will cause damage and improper function of clamp. Do not install the plastic spacer in the APS.
    2. Note: In order to set the clamp tension and lock timing, install all clamp lever components. Tighten lever until the cheek riser pillars do not fit into their respective holes. Avoid going too far past this point. Moving the lever will be stiff during this procedure. 
    3. Using a marking pen or whiteout, make a witness line from the bolt end onto the nut and stock body.
    4. Now make a mark on the bolt head (lever side) pointing to the rear of the stock.
    5. Holding the nut in place, remove the bolt and lever arm.
    6. NOTE: The nut is a 2 start thread, attempt to reinstall the bolt in the same orientation as it came out.
    7. Rotate the lever arm to be parallel and pointing in the same direction as the marking on the bolt head.
    8. Install the bolt and lever arm to the locked position.
    9. Unlock and test fit the clamping tension with the cheek riser installed with out the retaining pins.
    10. To make small tension adjustments repeat steps 5 to 9 moving the lever arm one or two spline positions on the bolt at a time counter clockwise if more tension is needed.
    11. Once desired tension is met, compress one pillar spring, insert riser into stock, install retaining pin and release spring tension.
    12. Compress second pillar spring as much as possible and install second retaining spring. If the spring is not compressed enough away from the retaining pin hole the pin will be trapped in-between coils making proceeding removal extremely difficult.