I think that this design is way to complicated and heavier than it has to be. Get rid of two washers and add a rubber disk (with a trapeze shape) in front of the first washer. Have a look at the shape of the rubber disk on this piston. Works like a charm. http://img709.imageshack.us/img709/199/pisto...

The rof would depend on the pressure and the strength of the spring. There is a lot of potential to tweak this design to high rof and/or power, given that you regulate the air source to a certain pressure.

The idea behind the mechanism is that it also runs on low pressure. At it's maximum opening point (on the right) the bolt opens on the left side a little bit. A larger surface area is exposed that forces the bolt back until it reaches the exhaust ports and the cycle starts again.

Why should I build something that JSR has already proven to work? I'm more interested in doing things that haven't been done before.

This is my idea of a self cocking, 3-way bb gun that I've had in my head for quite some time. In general it is a 3-way paired with a pop-off valve.
A trigger mechanism to catch the bolt is not included in the animation but that shouldn't be so hard to build in real life.

I thought this might be of interest for this topic.

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The pipe that reaches from the plug to the bottom of the fe is screwed into it, try if a fitting fits with the threads. If so, cut away the original release valve from the plug and screw the fitting into it from the top. It worked with my fire extinguisher but there will be some bottlenecking due to...

Do you still have the original plug that came with the fire extinguisher?

Let's see... 5% = 60$, then the product you want to buy is around 1200$.

Do you want to buy something like this?

What about the "not spoon feeding" policy of this forum? A dumbed down version of a cannon is still a cannon. I have recently set a how-to video on YouTube to not listed because people started to mess around. One guy told me that he lost a finger (he was trolling but I was shocked at first) and anot...

Guys, it has all been done before....



...a six shot flashlight sized flare gun, here you go....

Since I am the author of the video and have some experience with hot glue pistons, I can say that they are very durable even under high pressure. There are different kind of hot glues on the market, the stuff that was used in the video is very tough. With a reinforcing metal washer between the seali...

A nice build indeed, but I don't see the advantage over a simple coaxial design, regarding opening time and handling.

A short "fat" chamber and inline ports would be the better choice for a QDV style valve.

You should definitely use a longer barrel. Does the ammo have a snug fit in the barrel? Too much blow by hurts performance as well.

Look at 0:35 sec, you can clearly see the BL-520
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