How to Make a Real Gun

Because of strong gun laws, many enthusiasts are interested in the possibility of making their own guns. A firearm may be made by a non-licensee provided it is not for sale and the maker is not prohibited from possessing firearms, according to the ATF. Building a primitive firearm is as simple as putting a bullet in a pipe, and building more complex firearms is a possibility for those willing to invest the money and effort. Always use extreme caution when handling or assembling firearms. See Step 1 for more instructions.

Method 1 of 3: Making an Improvised Pipe Gun

1

Get the necessary parts. The United States Army provides literature about improvising small arms with a minimum of readily-available simple parts, for use in emergency combat situations.^[1] To build a basic 9mm gun, you'll need:

• 4-6 inches of quarter-inch nominal steel pipe, threaded on each end
• Two steel pipe couplings
• A quarter-inch pipe plug
• two rubber bands
• A thin metal strap at least 5 inches long
• A nail
• Two wood screws
• A drill
• Please note: If you attempt to fire a bullet from a piece of pipe that you're holding in your hand, and that bullet doesn't fit snugly in the piping, or the pipe isn't thick enough to withstand the pressure of the expanding explosion you're creating by striking the bullet, the pipe is going to blow up in your face, injuring or possibly killing you. Use extreme caution.
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• Method 1 of 3: Making an Improvised Pipe Gun

  2
  Use a 9mm bullet as a guide. Casings come in different sizes or calibers, and you need to use the size of the bullet to measure the opening in pieces of prospective pipe. 9mm is a common round size, and it's 0.38 of an inch (38 caliber). If you want to fire a .38 round, then, use a 0.38 caliber round as the source for all measurements. Find a suitably-sized drill bit matching the diameter of the projectile or a pre-drilled piece of piping. 

• Method 1 of 3: Making an Improvised Pipe Gun

  3
  Make sure that there are no cracks or other flaws in the pipe or fittings. Check the inside diameter of the pipe, using a 9 mm cartridge as a gauge. The bullet should closely fit into the pipe without forcing, but the cartridge case should not fit into pipe. The outside diameter of the pipe must not be less than 1-1/2 times bullet diameter (0.536 inches; 1.37 cm).

   Drill into the coupling to remove the thread. Make a 9/16 inch (1.43 cm) diameter hole 3/8 inch into one coupling to remove the thread. This drilled section should fit tightly over the smooth section of pipe.

  • Next, drill a 25/64 inch (1 cm) diameter hole 3/4 inch (1.9 cm) into the pipe. Always use the cartridge you intend to use as a gauge. When a cartridge is inserted into the pipe, the base of the jacket should be even with the end of the pipe. Thread the coupling tightly onto pipe, drilled end first.
  5
  Drill a hole in the center of the pipe plug just large enough for the nail to fit through. The nail must be centered in the plug. Push it through until it's even with the squared-off end of the plug and round it off if necessary, using a file. 
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  6
  Bend the metal band into a "U" shape. Drill two holes in the flaps to fit diameter of the wood screws you're using. This will be used as a basic hammer to spring forward and strike the bullet, using the rubber bands to create tension, so you might also notch some small notches into the metal to keep the rubber bands from slipping. 
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  7
  Fashion a basic stock and handle from wood
  8
  Fix the metal bracket to the back of the gun. The idea is to position the nail in the metal bracket so it will swing forward and strike the bullet. When you've got it placed, screw it into the wood using the wood screws. To create tension, attach your rubber bands between the front coupling and the notches on the metal bracket.
• This basic design can work for ammunition of any caliber, as long as you change the measurements to correspond to the specific size of the bullet you're trying to fire.
• . The design is up to you, but it needs to be roughly an inch thick after being drilled and at least two inches longer than the assembled length of the pipe you're outfitting. Drill a 1.43 cm hole through the stock, about 1/2 cm from the top.
• Slide the pipe through this hole and attach the first of the two couplings to the front tip and screw the drilled plug into the back end of the pipe, the end closest to the handle.
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  Fire the gun by pulling the bracket back and releasing it. Remember: this is extraordinarily dangerous if it hasn't been measured properly. To try and ensure your safety, hold the pipe with a rag or welder's gloves, and place your shell or bullet in the pipe. Aim it at an appropriate target and strike the bullet squarely with the firing pin.