In soldering a catch on a gun barrel it will be necessary to tin the barrels and also the catch, and then to bind the latter to the barrels with strong wire; also bind the barrels for some distance from each side of the catch, making the ribs secure with wedges. To melt the solder, use heaters; these are generally made of copper with iron handles; or iron rods can be used, the ends being made red hot and inserted in the barrels. Cut some small slips of thin solder and place them on each side of the catch, using powdered resin. As soon as the solder melts, remove the heaters and cool the barrels.