GB190721926A - Improvements in or relating to Back Sights for Small Arms. - Google Patents

Abstract

21,926. Birmingham Small Arms Co., Driver, A. H. M., and Norman, G. Oct. 4. Sights.-Relates to back-sights for small-arms, and consists in means for so actuating the windgauge slide that a fixed abutment for the actuating- screw is dispensed with and the movement of the slide is considerably increased relatively to that of the screw. In the form shown in Fig. 5, the laterally-movable slide a is dovetailed to the part d, and each of the parts a, d is provided with a longitudinal groove of semicircular section. The parts f, f<1> of these grooves are provided respectively with left and right handed screw-threads, while the parts g, g<1> are plain and fit over the tops of the threads of the traversing-screw, which has parts h', h<2> respectively left and right handed to engage the corresponding screwed parts f, f<1>. The bar a and the body-part d each have a semi-tubular extension m, n adapted to fit within an annular recess l in the head i of the traversing screw in order to limit the movement of the bar a in either direction, as shown respectively in Figs. 5 and 6. By reason of the parts h', h<2> of the screw being left and right handed, the bar a moves twice as fast as the screw moves laterally. A spring q is provided to hold the screw-threaded parts closely together to prevent back-lash &c. The invention may be used with a wind-gauge fitted to the end of the leaf, and also with a bar carrying a peep-sight. The threaded parts h', h<2> of the screw may be of different pitch.