_Barrels most Suitable for Choke-Boring._—Laminated steel barrels are the most suitable for choke-bore guns, being harder and more tenacious than Damascus, and, therefore, resist the repeated strain of heavy charges better; they will be found to be more durable, and lead less than barrels of softer material. Barrels of plain steel, or decarbonized steel, so called, should never be used for choke-bore guns, as they are unsafe for guns with light muzzles. Decarbonized steel is most suitable for rifles, where great strength of metal is employed. The finest pattern in Damascus is not always desirable, as the excessive twisting necessary to make the fine pattern often weakens the fibre of the metal. _Freeing Gun Barrels._—It is often desired to free a barrel at the muzzle, or at both breech and muzzle; and the amount to be removed is so very little that it is hazardous to insert the boring bit for fear of removing too much. It is easily accomplished in this manner: Select a straight wood rod that does not quite fill the bore of the gun and saw a slit with a fine saw at one end, for about three or four inches, and parallel with the length of the rod. Cut strips of fine emery paper, or emery cloth, the width of which should be the same as the length of the slot, insert one end in the slot and wrap the projecting part around the rod, introduce this end into the barrel and work it up and down, if it be desired to finish the barrel that way, or turn it around by means of a bit stock or lathe if the finish is to be thus done. Many gunsmiths cast soft lead at the end of a rod, using the muzzle of the gun as a size mould, and after removing from the barrel, apply oil and fine emery, and with this work the inside of the barrel. [Illustration: FIGURE 28.] _Another Method._—There is another plan. Make a rod of soft pine wood that almost fills the bore and make a small hole, say about one-eighth of an inch diameter at the point where the saw kerf is to terminate. Cover this portion of the rod with good glue, made thin, and then roll it in the emery, the same as making an emery wheel or a buff-stick. When dry use it in the same way as the other forms of rod. When desired to increase the size, which will be necessary, a thin wedge can be inserted in the saw-kerf and pressed deeper in as the bore increases, or near as the rod diminishes its size. By wrapping the rod with fine twine where the hole is made there will be no danger of splitting the rod when the wedge is pushed in. The same form of wedge can be used in the rod first described, and at the same time the wedge will help keep the emery cloth or paper in place. The cut, Fig. 28, shows the rod as ready to receive the coating of emery.