Magazine Bolt Modification Instructions
NOTE: Before attaching the sling to your weapon clear the
weapon and double check to ensure it is unloaded.
The Mossberg 500 shotgun comes with a captive magazine bolt that is retained
by a star washer attached to the bolt threads. The purpose of this design is to
prevent loss or misplacement of the bolt.
To install the side sling mount plate the star washer retaining the magazine bolt
must be removed. This will eliminate the captive bolt feature, but will not affect
safety or reliability of the weapon at all.
Remove your barrel and locate the star washer inside the barrel ring.
Use a small screwdriver to hold the legs of the star washer in place while you
unscrew the barrel bolt from the star washer.
With the star washer removed you may now continue with your sling installation.
Install the barrel into the receiver. Place the sling plate ahead of the barrel ring.
Insert the bolt and tighten.