The L.C. Smith guns used a rotary bolt which engages the barrel rib extension. As the camming surface of the rotary bolt and bolting surface of the rib extension wear, the top lever spring gradually moves the lever to the left.
Various methods are used to fix this situation. The worn out rotary bolt can be replaced using good spare parts. The bolting surface in the rib extension can be built up with TIG or laser welding, and remachined to replace the worn metal. Sometimes, crude repairs are made by peening the rib extension, but this method is temporary at best. This is something to look for when buying an L.C. Smith.
https://www.lcsmith.org/content.aspx?page_id=22&club_id=43784&module_id=248706https://doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=397167&page=all
