June 20, 2013May 15, 2013 CZ shotgun gunsmith explains the difference in semi-auto o-rings and how to inspect, remove and install a new one. Share this gun video:Click to share on Facebook (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Tumblr (Opens in new window)