Cut the Crossbow Stock

• 1). Draw the design of the crossbow stock on poster board. Reference rifle-stock designs on-line to get an idea of the angles and the drop. The drop is the distance from a horizontal line extending backward from the top edge of the stock downward to the upper tip of the butt plate, allowing the weapon to be shouldered and comfortably sighted. Make this distance 2 1/2 inches. Make the overall dimensions of the stock 7 1/2-by-38 inches. Make the fall-away point, where the stock begins to drop down from the upper edge, forming the hand grip, 22 inches from the muzzle end.
  
  
• 2). Cut out the stock design with scissors and trace its outline onto a 2-inch plank of heavy oak or hickory. Because of the pressures involved, the stock of a steel crossbow cannot be made from soft wood, like pine.
  
  
• 3). Use a circular saw to cut away the larger dimensions of scrap and finish the rough stock outline with a router or shaper. Router the edges smooth with a 1/4-inch rounding bit.
  
  
• 4). Use a 1/2-inch V-groove bit and router a 1/2-inch deep groove all along the center of the entire length of the upper surface of the stock. This is the arrow trough.
  
  
• 5). Use a straight router bit and carve a 2-inch half-circular channel into the top edge of the stock. Make it at a right angle to the long axis of the stock, 2 inches ahead of the drop away point.
  
  
• 6). Drill a 1/2-inch hole through the stock vertically, starting inside the forward curve of the half-circular channel. Re-drill or use a long router bit and small chisel to channel a vertical shaft (the trigger channel) through the stock. It should result in a 1-inch-by-1-inch vertical shaft through the stock.
  
  
• 7). Mortise the trigger-pull channel which runs rearward and down at a 45-degree angle from the midpoint of the trigger channel. Drill a 1/8-inch hole through the width of the stock 1/2 inch below the upper center of the trigger channel. Drill another 1/8-inch hole through the width of the stock 1 inch up from the bottom of the stock and 1 inch rear of the rear edge of the trigger shaft.
  
  
• 8). Draw crisscross lines connecting the corners of the muzzle end of the stock. Drill a 1/4-inch-by-1 3/4-inch hole into the stock end -- to connect the steel bow.
  
  

Assemble and Build the Crossbow

• 1). Use a power hacksaw to cut a 24-inch piece of steel from a small automobile spring that is not wider than 2 inches. Hacksaw notches into the ends of the piece to attach the bowstring. Measure and drill a 5/16-inch hole in the center of the steel for the connecting bolt. Measure, mark and drill four 1/8-inch holes through the steel. They should be in a square pattern around the 5/16-inch hole, to be used as placeholders.
  
  
• 2). Cut the trigger release block from the 2-inch oak plank, using a cutting router bit. Make it an arched-door shape that is 1 3/4-inches square. Router two ½-inch channels at right angles in the rounded upper edge of the block. One channel is the arrow knock channel, and the other is the bowstring channel. Measure, mark and drill the connector hole through the release block, ¼-inch below its vertical midpoint to allow the block to extend above the top edge of the stock and catch the string.
  
  
• 3). Measure and cut a ½-by-1/8-by-6-inch piece of steel. Mark and hacksaw alternating 1/4-inch cuts halfway through the width of the piece and 3/8-inch apart. Wrap the piece around the shaft of a heavy screwdriver that is held in a vise. Slide the two surfaces together at the cut-lines, forming a loop. This is like sliding two half-cut boards together, producing a connection that is still as wide as the original pieces. Practice this on a piece of ribbon or thin strip of paper, first. Cut the piece to a 3 ½-inch overall length. Bend a curve for the trigger in one end and fold back the other end toward the trigger to form the 45-degree release jam that is inserted against the release block. The fold-back should be 3/4-inch long.
  
  
• 4). Insert the release block in its channel and bolt it in place with a 1/8-inch machine bolt. Rotate the release block, ensuring that it will rotate forward and backward freely. Insert the trigger into the stock and bolt it in place with another 1/8-inch machine bolt. Test the trigger release by rotating the release block backward and rotating the trigger forward. The release jam should hold the release block in place until the trigger is pulled. The release block will be rotated forward by the tension of the bow, releasing the string and firing the weapon.
  
  
• 5). Attach the steel bar to the end of the stock with a 5/16-by-3-inch lag bolt. Drill and screw in the four 1/8-inch placeholder screws. Tie six-cord flax thread or 5/32-inch flexible wire cable tightly around the end notches in the bow. Test the bow by locking the release block and drawing the string back, locking it over the release block and into the string groove on its backside. Pull the trigger and test the firing performance. Alter the joints and fittings for a smooth trigger pull. Apply stain and polyurethane finish to the stock.