Sear Springs.—Sear springs are made for right and left hand locks. The side-action or bar-lock springs are shown in [Fig. 58], and the back-action lock springs in [Fig. 59]. In one kind of back-action lock there is used a bent spring similar to the bar-lock spring which is shown in [Fig. 60]. It will be observed that the lower branch of this spring is longer than that which is used in the bar or side-action locks.
Figure 55.
How to Forge Mainsprings.—If the gunsmith desires to forge his own mainsprings he must select a good quality of spring steel, as cast steel is generally too quick or fiery for springs that have as severe a duty to perform as a mainspring. Get the steel of the same thickness as the mainspring and of a width equal to the spring and the pivot that goes through the lock plate.
Figure 56.
Draw the spring out carefully over a fire that has been burned enough to free it from sulphur, if bituminous coal be used, and be very careful not to over-heat the metal. Form to shape with any tools or means that may be at hand.
For straight springs, as some kinds of pistol and gun-lock springs, procure steel of the thickness and width of the spring at the widest and thickest end, and draw down to the requisite width and thickness of the smallest end.
