Your First Step in making the crossbow is to draw a 5 1/2 x 9-in. grid of 1/2-inch squares on paper. Then copy the outline of the pistol stock (side view, Fig. 3) using the 1/2-in. squares to enlarge it. Also copy the outline of the cocking side plate and trigger guard. Use carbon paper to transfer the pistol-stock drawing to 1 1/4-in-thick maple or walnut stock. After sawing the stock to shape drill a 1/2-in. hole up through the center of the pistol grip and then insert a 1/2-in. dowel, gluing it in place. This will prevent the grip from splitting with the grain.

Make the Two Cocking Plates by first transferring your full-size drawing of each to 1/8-in-thick steel. A series of prick-punch marks spaced about 1/8 in. apart along the outline will serve as a dotted guide line to follow when cutting the steel. The latter is done by using a jigsaw or hand coping saw fitted with a fine-tooth metal-cutting blade. (In a pinch you can rough-cut these parts to size with a cold chisel, then file and grind them to the correct dimensions.) Now clamp the two plates together and drill the holes for the rivets, made from the shanks of 16d (3 1/2-in.) common nails. Countersink these holes so that the rivets set flush.

Next rough-file down each side of the stock grip to a thickness of 1 1/8 in. Clamp the cocking plates to the sides of the grip so that they are positioned as shown in Fig. 3 and drill rivet holes through the grip. Then mark the grip for mortising the plates into it by tracing around the plates with a sharp pencil. Remove the plates and cut around the mortise edge with a gouge or narrow chisel making it slightly undersize. Make several cut lines across the grain to break up chips and establish the 1/8-in. depth of the mortise. Hollow out the mortise by hand chiseling or with a router bit in a drill press.

To aid in forming it symmetrically, make a couple of cardboard templates (Fig. 3B) to check the roundness of the grip. Fair off the grip toward the top and round the corners of the stock.

Mortising for the Trigger Mechanism can be done now or after the plates are riveted to the grip. In either case lay out the size of the mortise on top of the stock and bore it out, starting with the end holes and working toward the center with holes overlapping (Fig. 3C). Set the drill-press depth gauge to avoid boring too deeply. Chisel the sides of the mortise smooth and square the ends.

By the way, the nails can be softened for easier riveting by heating the ends red hot with a torch and allowing them to cool slowly. Now rest the pistol grip on the vise anvil, nail heads down, and rivet the cut ends. Turn the stock over then and hammer the nail heads into the countersunk holes. Finish by filing the rivets flush with the plates.

The Trigger Mechanism Itself is started by first making the notched wheel and detent, following the same procedure used when making the cocking plates (note that these parts are shown full size in Fig. 5). Forge the trigger from a 5/16-in. round steel rod by heating it red hot and hammering it to shape. Flatten the upper part and shape the trigger section with a ball peen hammer (Fig. 3E). Cut, clamp together and drill the holes through both side plates

Make pivot posts from nails, shouldering them on a metal-turning lathe (Fig 10). Lacking a lathe, you can do this work on a drill press by gripping the nails in a chuck and filing the ends down to fit the plate holes. Use a file having smooth or safe edges to make the shoulders square and sharp.

Here's How the Trigger Mechanism Works: The slot in the notched wheel is held in position for accepting the bowstring loop by a small helical spring beneath the wheel and anchored to the left plate with a screw (Fig. 9). The flat spring which holds down the detent is bent from a hair curler. The detent locks the wheel against the pull of the cocked bowstring. The lower end of the detent, pressing against the back of the trigger, holds the trigger against its stop. When pulled, the trigger pushes back the detent, the detent releases the wheel and the bow-string springs forward and fires the bolt.

When assembling the trigger mechanism, first rivet the pivot posts to one side plate. Then add washers, working parts and upper washers. Before riveting the second side plate, test the action by pressing the wheel forward with your fingers until it stops, checking to see if the wheel releases when the trigger is pulled.

Now hammer the curved spring to flatten it on the bar. Then draw another curved section over the bar for straightening. Straighten 15 in. of the spring, then nick it on a grinder and break it to length.

The unstrung bow should be bent somewhat in a reverse curve, as shown in Fig. 6. Bend the ends by spanning them over vise jaws opened to 1 1/4 in. and hammering them with a ball peen. Grind a taper on the lower edge of the bow toward the ends so that the bowstring will clear the channel. Also grind the nocks (notches) at the ends of the bow to take the bowstring. To strengthen the bow, straighten a 6-in. length of spring steel and taper down the thickness toward the ends. Center this spring leaf behind the bow and secure it with loops of bind wire. For an even stronger bow you can put a 10-in.-long leaf between the main bow and the 6-in. leaf.

The Spring-Steel Bow was made from the coiled spring of a hood hinge from a 1953 Ford and was obtained from an auto wrecking yard. It is straightened by gripping it in a vise (Fig. 6A), lifting the free end of the spring and sliding a steel bar under it so that the latter rests on the vise jaws. Now hammer the curved spring to flatten it on the bar. Then draw another curved section over the bar for straightening. Straighten 15 in. of the spring, then nick it on a grinder and break it to length.

The bow is held in place with clips bent from 1/8 x 1-in. steel (Fig. 2C). A lag screw passing through the clips into the end of the stock locks the bow between the clips. Two machine screws passing through the forward end of the stock, and at an outward angle toward the bottom so as to clear the lag screw, fasten the Pistol Crossbow clips and channel to the stock.

To Make the Channel detailed in Fig. 2A, bend 1/16-in. sheet metal as shown in Fig. 3A, then trim and file the upper edges. Cut the notch at the rear of the channel with a file and drill the holes for the screws. The center screw also serves to fasten the forward end of the trigger guard, while a couple of round head wood screws near the back bear against the sides of the channel, their heads bearing on the top edges.
Make the trigger guard from 1/8 x 3/8-in. steel or aluminum bar stock, bending it as indicated in the drawing of the gun stock.

In assembling the pistol, place the trigger mechanism into its mortise, set the channel on top of the stock, insert the screws, then add the bow, clips and trigger guard as shown in Fig. 2.

Make the bowstring (Fig. 6B) by bending one end into a loop just large enough to slip over the end of the bow. Holding the loop in a vise, wrap half the length of the short cable with spooled binding wire. Then fray out the cable end, bend the strands back over the binding and wrap these also with wire.

The Goat's Foot or cocking handle (Fig. 7) is shaped from hardwood and fitted with a half cylinder made from a hardwood dowel which bears on the cocking bolt. The hooks are bent from coat-hanger wire passed through an off-center hole in an iron bushing.

A spreader made from a dowel is fashioned to make a sliding fit between the hooks and the outer edges of the channel. The goat's foot cocks the crossbow by drawing the bowstring back and setting it in the wheel notch which is attached to the trigger mechanism. Once the crossbow is cocked the goat's foot is removed. For easy carrying, the goat's foot can be fitted with a hook and you can hang it from your belt.

Finish the wooden parts of the pistol and the goat's foot with three coats of floor sealer. Polish the metal parts and blue them with bluing compound obtainable at gun shops.