This L&R Lock Company M. Medina Hawken percussion lock was designed by the late Don Stith. Notice the early style rounded front edge vs. the square corner found on later locks. The lock plate also has a bit more curve from end to end than later percussion locks. The percussion hammer has cast-in engraving with a 1.8" throw. The lock plate is 4.5" long by 0.96" tall.
Fitted with a fly detent for use with set triggers. A swivel link with integral pins hooks into the cut-away tumbler arm, to allow simple disassembly. Beware: the link must not be installed backwards, or the link and mainspring will be broken on first use. The small diameter pin hooks into cut-away tumbler arm, and “S” orientation allows essential mainspring clearance. Don’t break it! Plate is finished bright inside and out. Cut the plate for the drum or patent breech. Fit a thin card pattern to the breech, trace it to the lock plate, file to fit. It is easier than it sounds. The hammer has a 1.8” throw, for use with octagon barrels from 15/16” to 1-1/8” at the breech.