The Patent Breech.—The patent breech has been the subject of much discussion and much experimenting, some experts claiming one form to be superior to others, and then again there are those who set the patent breech aside and claim that the old flat-faced breech-pin is as good as any ever yet made. The formation of the base of the breech-loading shell has been called up as evidence in favor of the latter claim. The two forms are called in question, and then the query is made, “Does not the breech-loader shoot better or as well as the patent-breeched muzzle-loader?” But the patent breech is in favor with the mass of those who use the muzzle-loader, and no doubt has its advantages. The attempt has been made to form the interior base of a cartridge for breech-loaders upon the model of the interior of a patent breech, but thus far has not come into very extensive use.
Form of the Chamber or Cup.—While many forms of the chamber or cup of the patent breech are in use, the most simple form, and the one easiest to make, is that of an inverted elliptical cone. This form may be represented by the shape of an acorn if it were cut off even with the top of the cup. The shape is also one that will not weaken the breech nor affect the strength of the thread where it enters the barrel. The tool to shape it is easy to make. Turn a piece of steel the exact shape the “cup” is to be and then make a cutting tool of it by filing a groove on two sides, exactly like a flat drill of the required elliptical form, but with a “bulge” or cheek left on each side, and then file a groove mid-way in this cheek from point to base, and make it so as to form two cutting edges on each side of the cut first made. Each prominent part must be formed into cutting edges, like the cutting edges of a conical-shaped cherry to cut out bullet moulds. The cut, of bullet cherry, [Fig. 71], Chapter XXVII, shows the way to make this tool.
With this form of “cup” there is great solidity of breech, and there need be but little fear of miss-fire or hang-fire in shooting, if the gun be properly loaded.
CHAPTER XVII.
TOOLS FOR BREECHING GUNS.
Breeching Reamers.—The form of breeching reamers is shown in [Fig. 35]. The extension is supposed to fill the bore of the gun, and when it does so the tool will make a cut that is straight and true. When this extension does not fill, then slip a brass ferrule or a piece of tubing on it, or it may be even wrapped with a piece of card or strong paper, as mentioned in case of taps that have extensions smaller than the bore of the gun.
Figure 35.
The size of these reamers must be to suit the taps; that is they must be of a size corresponding to the tap if the thread were removed. The length of the extension may be about an inch, and the cutting portion of a length to correspond to the length of the breech-pins, for when using them where the reamer has entered the barrel until it is flush or even with the length of the cutting part, it is evident that it has penetrated as far as it ought to go. Be careful to keep the reamer well oiled when using it to ream out a breech.
In making these reamers, turn them to the size and shape, and then file four spiral flutes, equi-distant from each other, with a small round file, but remember to file them “right hand,” like a right hand screw thread. About a quarter’s turn in the length is sufficient. The end where the cutting is done must be “cut back” between each flute, so as to make a cutting edge, or lip. The flutes serve to carry the chips away from the work, and prevent clogging. Above the end of the cutting portion, the reamer may be turned down to a size a little larger than the extension, and it will be then a very easy matter to nicely cut the flutes with a round file, as directed.