How to Build an Air Gun

What you need

• 1" pvc pipe
• pvc cement or glue ( I don't think it matters)
• (2) 1" pvc end caps
• (1) 1" pvc 90 degree elbow
• (2) 1" female to 3/4" male (threaded) adapter (only the male end needs to be threaded)
• (1) 3/4" ball valve
• (1) Air valve from a bike tire tube (cut it off the tube, make sure there is some excess rubber around it)
• A tube smaller than 1" that will work as your barrel
• A drill
• 1” screw

Instructions

1. Take one end cape, and drill a hole in the bottom of it, large enough for the stem of the bike valve to fit through. The excess rubber around the base of the stem should be glued to the inside of the end cap. This way, you can use the bike pump to pressurize the gun, and no air will leak out. It is important that you glue the valve well.
2. Take your 1” pvc pipe and cut 3 different lengths. One should be 5” long, one 2” long, and the other about 7” long. The 7” piece will serve as the pressure chamber. However, these lengths are just what I used. You can change them if you want, I don't think it will make a big difference.
3. Now glue the previously assembled end cap to one end of the 7” pvc. On the other end of the 7” pvc, glue the 90 degree elbow joint. On the side of the elbow joint, glue the 2” length of pvc pipe, and then on the other end of the 2” piece, glue the 1” to ¾” adapter. Only the side that is ¾” should be threaded, and male. The side that is 1” should be female, and not threaded.
4. Now you have the pressure chamber completed. Once it dries, screw the adapter into one end of the ball valve. Close the valve, pressurize the air chamber, and check for leaks. Fix any leaks that you find.
5. Now, take the other adapter and screw it in tightly to the other end of the ball valve. I did not glue the adapters into the valve because the valve costs about $8 and I want to be able to use it on other things, but you can glue it if you want.
6. Now, take the 5” pvc length, and glue it to the female side of the adapter.
7. Now is the hard-to-explain part. Take the second 1” end cap, and the smaller tube you want for a barrel. If you watch my video, you will see that at the end of the 5” pvc length, the barrel gets smaller. So take that tube, and find a drill bit a little smaller than it. Drill a hole in the center of the end cap. The smaller tube serving as you barrel should fit in tightly.
8. Now take the end cap with the hole for the barrel in it and put it on the other end of the 5” pvc length, that is also connected to the adapter. When the end cap in completely on, mark where the end of the end cap is on the length of pvc. Take the end cap off, and drill the 1” screw into the 5” length of pvc near the mark you made. The screw shouldn't go all the way through the tube, if it does, then find a shorter screw.
9. Now you are ready to finish the assembly. Put the barrel tube through the pvc end cap (the one with the hole in it), and put the end cap back on the end of the 5” piece of pvc. Once it is completely on, push the barrel tube as far in as you can, until it hits the screw. The screw prevents any projectiles that you put in the barrel from rolling out the other end.
10. Now, take a bike pump, or compressor, and pressurize the air chamber via the bike valve. Once it is pressurized, take the bike pump off, load a projectile, and you are ready to shoot. To shoot, just open the valve. .