Joints for Bullet Moulds.—Simple as it may seem, the joint of bullet moulds, unless produced by the manufacturer, who has ample tools at his command, is not often well done. The want of the proper knowledge how “to lay out” such a joint may be the excuse for ill-fitting work. Yet it is easy enough, only “know how.”

By reference to the cut, Fig. 63, the joint and one side of the body of a bullet mould, it will be observed that the line A is the surface where the two halves abut or come together. The line B is drawn at right angles to this and in the diametrical centre of the round projection that is to form the joint. At the point of intersection of these two lines, or in other words where these two lines cross each other, make an indent with a sharp-pointed prick-punch, and there drill a hole of the size that the rivet is to be made.

Fig. 64 shows the finished joint ready to receive its mate and be rivetted together. After the hole for the rivet is made, a tool must be used to “sweep” or cut down the surface at C, and also leave a sharp and smooth shoulder as shown at D.

To make this tool, select a piece of steel, centre it in the lathe, and turn one end—say an inch or so—of the same size that the joint is to be. In this end drill a hole lengthwise, but exactly in the centre, of the same size that the rivet is to be. Cut teeth on this end, and temper as any tool for cutting metals. Insert a steel pin in the hole, leaving it projecting half an inch or more, and the tool is ready for use. The cutting end of the tool is shown in Fig. 65. Of course the other end must be fitted to the lathe chuck or a bit-stock in order to use it. Insert the projecting end of the pin in the hole A, drilled for the joint, and by means of the lathe or bit-stock, cut down each half of the mould to about half of its thickness. The outer circle or cut of the tool will be a guide to which to file the circle of the joint. If the cutting end of the tool be made a little convex it will form the surface of the joint a little hollowing, and a better fit will be the result.

Countersink the outer ends of the hole, insert the rivet, and rivet them together. The perfection of the joint can be ascertained by opening and closing the mould a few times, removing the surface where the rubbing is apparent, with a fine-cut file.

If the surfaces of the two halves at B, Fig. 64, do not exactly come together, and the material be brass or malleable iron, a few blows with a hammer will insure close contact. It may be necessary to say that the surface at B must first be made true and square, so that the two halves will fit closely, and then “lay out” the joint from this surface.

If there be many bullet moulds to make the circle of, the joints can be made by means of a cutter revolving in the lathe. Make this cutter about two and a half inches in diameter and half an inch thick. Cut teeth in the sides as well as on the circumference. Fit it in a spindle so it will revolve. After the joint is drilled fit it so as to turn on a pin fixed in a piece of iron that is held at one side of the cutter. By feeding the mould up to the cutter the surface or shoulder is cut where the two portions of the joint come in contact when opened. By turning the mould slowly around a portion of the circle is cut, say about one-half. Remove the mould from the pin, invert it, and the remainder of the circle can be cut; the whole “round” and the abutting surfaces being produced at two cuts; a little smoothing up with a file being necessary to finish it. This operation and the cutting is shown in Fig. 66.

How to Make a Ball Cherry.—The term “cherry,” as applied to the tool used to make the mould for spherical balls or bullets, was no doubt borrowed from the fruit of the same name—in fact the fruit and tool are very similar in form and size. To any one not conversant with the process of producing a sphere in metal it seems a very difficult operation, but nevertheless it is very simple, and only requires a little knowledge and experience to make a cherry to fit any bore of gun. This is the rule governing the operation: A rotating body is passed through a properly-shaped circular aperture in a flat steel die that is held with its upper or cutting in the same plane as the axial line of the body rotating. That’s all.

Now, to make application of the rule. Suppose we have a rifle of a certain bore to which is to be fitted a round ball. First, take a piece of steel, we will say about one-quarter of an inch thick, about one inch wide and about six or eight inches long. An old file of good quality, with the temper drawn and the teeth ground away, may answer the purpose. It should be annealed as soft as possible. With a drill make a hole near one end, but a little less in size than the bullet to be produced. With a taper half-round reamer cut out the hole until that side of it which is to be the upper or cutting edge is exactly the size of the bullet desired.

The advantage of using this taper half-round reamer is the hole is made perfectly round, and at the same time the taper of the reamer gives a bevel to the hole that forms a good, strong and effective cutting edge. With a file cut out a portion of the tool of a V shape, bevelling the edges the same as the hole as shown in Fig. 67. This V may be either cut on the end, a side of the tool, as shown, but in use it is preferred to be cut on the side, as then, if necessary, the hand can find a hold on that end to assist it in operating. When done, temper for use. For the cherry, turn a piece of steel in the lathe to fit a chuck. Half-inch octagon is perhaps the best size of steel from which to make cherries of less diameter than half-inch, and the length about six inches. The end on which the cherry is to be made is roughly fashioned into a ball, leaving the end where the centre supports it to be removed by the lathe tool or by filing.

When fitted so that the rough blank will be held firmly in the chuck, run the lathe at moderate speed, set the T rest so that the steel die can be held on it about level with the under side of the rotating blank. On the rest lay the die, and press the opening so as to receive the rough sphere, applying oil and not pressing too hard. Let it gradually scrape its way through the circular aperture, the V-shaped opening in the side receiving the stem to which the cherry is attached. In Fig. 68 is shown the finished blank after being passed through the die. If it be preferred the die may be held in the hands and not supported on the T rest. Take care to supply plenty of oil to the work, as this will prevent scratching or tearing the cherry while being formed. It is well to make two of these holes, one at each end of the piece of steel, roughing the blank with the first, which is a little larger than the one used to finish the cherry of the exact size. When this tool gets dull grind on the upper or cutting edge, but not too much, as it will enlarge the hole, and the result will be to make a larger cherry.

To form these blanks into cutting tools, a copy can be taken from the cherries as sold to the trade. Bear in mind to leave the grooves deep enough to receive the metal cut from the blank mould when in operation.

It will be observed that the cherries as purchased (Fig. 69) do not have their cutting edges terminate in that portion of the mould, but usually on one side. This is done to insure a perfectly spherical form by having a cutting side operating at the bottom of the hole while it is being formed. It is somewhat difficult to make this form of cutting edge, and some patience and care must be exercised or the blank may be spoiled.

Every mechanic knows how nice and rapidly a well-made drill will cut. Suppose this form of cutting edge be applied to the bullet cherry. It is no matter if this cherry be round or of conical form. Fill two cutting edges like a drill on opposite sides of the blank from the shank to the end of the cherry. It is evident that here the two rounded portions that are left on each side of the cutting edges to be removed that the tool is nothing more nor less than a peculiar shaped drill or reamer that might form an internal sphere. But as this form could not well be applied between the sides of blank bullet moulds, and as the full rounded sides would not permit of these edges cutting, then form the rounded surfaces into similar cutting edges like the two first made, only not so large, making three or four on each side, according to the size of the cherry. These cuts can very easily be made with a fine cut three-square or half-round file. A cherry of this form for a round ball is shown in Fig. 70, and one for a conical ball in Fig. 71.

In using a three-square file, to get a fine-cutting edge that will make a sharp V cut, grind away the teeth of one side. This will remove the slightly rounded or blunt edge as usually made on this form of file. By grinding thus, two acute cutting angles can be had from one file. If they get a little dull on the sharp cutting corner, a little grinding will restore the edge and make it sharp again.

Tempering Bullet Cherries.—In tempering the cherry do not leave it too hard, and be careful not to temper too hard above the spherical portion. Leave the shank softer, as it will be less liable to break. It is not necessary to shape the shank so as to exactly conform to the shape of the V opening in the forming tool, for, as the edges of this opening have been bevelled the same as the opening that shapes the cherry, they will act as cutters, and will reduce the shank to conform to the V. It is well to mark the cherries in some conspicuous place on the shank, with their size in hundredths of an inch, the same as cartridges are numbered, and also mark them with the number of round balls to the pound, as was formerly in vogue among gunsmiths. The finished cherries, as purchased from dealers, are so numbered.

Cherries, as purchased, have shanks fitted to be used with a bit-stock, but if the gunsmith fits these tools to be used in a lathe chuck that has a round hole, necessitating a round shank, and also wishes to use them in a bit-stock, he can fill up the square hole in the bit-stock by brazing therein a piece of iron, and then drilling a round hole to fit the tool.