ll it appears that every Hammerless double gun I currently own, including a Birmingham built J P Clabrough;
 has had its sears so reduced in length (by bad manufacture or ham-fisted/repeated trigger regulation) that the correct regulation has been lost and the sears need replacement or extending by a knowledgeable gunsmith with a good TIG welder.
None of them will however be going in to be welded up. Note Though I have owned both in the past I do not currently own either an L C Smith or a Parker. One time about 59 years ago at age 16 on the first Double I ever owned I loaded it without cocking. I don't recall now what kind of game I encountered but when I pushed off the safety & pulled the trigger nothing happened. I learned my lesson well, I have never again loaded a double without the locks being cocked. I don't "Slam" my guns shut & even so you would have to slam it mighty hard for the hammer to come down with enough force to fire the shell. On my Favorite make of gun the firing pins do not protrude, but depend on inertia of the hammer to fire the gun. I don't believe you could close this gun hard enough to fire it with uncocked hammers, now "That's Good Gun Design" even if it "Ain't" British.