A couple of years ago my son was studying the Medieval age in Social Studies. His teacher assigned the class a project to construct something that represents that era and write a paper on it.
I helped him build a homemade crossbow that really works! I was concerned he might not be able to take it into the school, but he had specifically asked his teacher if it was OK for him to build a crossbow for his project and she said yes.
The morning we took it to school, his mother accompanied him with the crossbow underwraps to the office. Once inside they asked to speak to the principal and explained to him the situation. My wife said his eyeballs almost popped out of his head when he saw this thing!
He agreed that as long as the crossbow did not have any arrows (known as bolts in crossbow lingo) with it, my son could take it to class. His Social Studies teacher awarded our efforts with a really high mark and he got an A in Social Studies that semester.
We ordered a package of crossbow bolts made for a crossbow pistol and took some target practice with the makeshift weapon at a nearby farm. It worked great and would make an excellent short-range survival weapon for taking small game.
I wish the crossbow was entirely my idea, but I have to give credit to Ron Hood for that. Ron makes survival videos that are very detailed and shows in one of his videos how to build a crossbow similar to this.
One word of caution. This crossbow has NO SAFETY. It would be very easy to fire the weapon inadvertently. Therefore I recommend if you decide to build one to not load it until you are ready to fire. Make sure no one is down range of you and that the weapon is pointed in a safe direction when you are loading it.
Here is a little more detailed information on how to construct the crossbow. We used a 2×4 for the stock. The only reason for that was to make it look like a medieval crossbow. For a survival crossbow you could make the stock from pretty much any tree about 2 inches in diameter.
Make your bow first. We used rattan because we had some and it makes a great bow. Again, you can use just about any wood. Hickory has pretty good qualities for a bow. We used parachute chord for the bowstring.
You will want to measure about half to length of your bow down the stock. This is where you should cut into the stock to make your trigger mechanism. Measure approximately another 4 inches past the end of the trigger box and this will give you the overall length of the stock.
Once you have cut in your trigger box you will need to drill a hole down through the stock at the front edge of the box. The top part of the hole should be round. However, on the bottom of the stock, you will want to elongate the hole. Once you put your trigger in place the elongated hole on the bottom will allow your trigger to rock forward and the string to slide off and engage the arrow.
Next, cut a T shaped piece that fits down through the trigger hole and protrudes about an inch or so out the bottom. Cut a notch in the front of your stock to put the bow in. The notch should allow for a tight fit of the bow. I put a couple of screws in the front side of the stock and used parachute cord to lash the bow into place.
I lashed a piece of wood to the top of the stock to make an arrow keeper. This will hold your arrow in place and ensure that the bow string engages the arrow properly upon release. If you prefer, you can carve a groove down the top center of the stock for your arrow to ride in.
We stained our crossbow to give it an authentic look. Now you can either hand make your own arrows (bolts) or you can purchase some practice arrows that are made for crossbow pistols. Check with your local Army / Navy surplus stores.
I can not stress enough how careful you have to be with this piece of equipment. Again, there is no safety. Do not load until you are ready to fire and keep it pointed in a safe direction at all times!