This high quality patchbox release kit is made for use with brass, iron, or nickel silver patchboxes. The kit includes four precision steel parts, two unplated steel screws, and fully illustrated instructions.
The end of the catch has a square shank, to prevent rotation in its hole in the lid. Drill and countersink the lid, insert the square shank, and carefully peen and round the end, permanently riveting it to the lid, concealing the square shank. The catch is made too long. File a tightly positioned notch, and bevel the end before installation.
The catch spring has a blank end. File an appropriate hook to fit the notch you file in your catch. Made with an integral spring, you may thin the spring by filing it, not too much.
The long flat spring is called a “kick open spring". Concealed under the head of your patchbox, it will throw the lid open each time the release is pressed.
Precision steel parts, such as these, are expensive. Made with your choice of a brass or steel release button, it is appropriate to use a brass or steel push button release on your brass, nickel silver or iron trimmed longrifle.