Step 8: Finishing Up
Once your chamber is filled with pressure, you need a way to trigger the valve. You can use a nail or other small object to push the pin in the schrader valve or you can get creative and make an attachment like I have. It's basically some random brass fittings with a bolt going through the middle and a spring that threads on the schrader valve. I can push the bolt down in to the schrader pin, firing the gun; the spring then returns the bolt to its original position. Pictures of this adapter are below. I wont go in to how to make one as you need fittings that I'm not sure everyone can easily find and I'm not even sure what they are called, I just had them spare in my box of brass fittings. In the mean time, find a creative way to make your own attachment or trigger for depressing the schrader pin. If you remove the head attachment from an old bike pump, you could trigger the gun by pulling up the lever on a pump head attachment like this as it engages a pin that moves forwards and depresses the schrader valve pin.
There is one last thing: the lamp reflector head that I got you to unthread from the flashlight body back in step 3. You can either remove the glass/plastic front and reflector from inside the head or you can leave it in place. If you remove the glass and reflector, it will allow you to shoot the gun while it is threaded on to the flashlight (I have done this for my green flashlight BB gun). If you leave it in place, the flashlight gun will give the appearance of a flashlight when the head unit is attached to the flashlight body, but you can't load and shoot the gun until you unthread it from the body as it obstructs the barrel.
Air is leaking out your barrel: your sealing face on the piston needs replacing/the barrel is not centred inside the flashlight body and is on some angle/the sealing face on the piston is on an angle/the sealing face is the wrong type of material
When you depress the schrader pin, nothing happens/all the air comes out the schrader and not the barrel: your piston is too tight of a fit and is stuck/your piston is too loose and too much air can move between the piston and inside of the flashlight body/you're not using enough pressure (50PSI should be more than enough for the valve to work)/not enough air is flowing out the schrader valve fast enough.
Performance is bad: probably a combination of the problems above.
Any other problems? Send me a message.