SpudFiles

I was thinking about a pneumatic revolver (pistol) and came up with a quick valve design I think the picture explain it. Spudfiles pictures don't work for me though, so I can't tell if it uploaded properly.

Basically, the air pushes back the ram at the bottom, moving back the bolt at the top, until the top chamber is filled. Then the ram is vented, the one way valve keeps the chamber full and the bolt movves forward and vents the chamber.

Any glaring problems I've missed or better ways of doing it?

Xerxys wrote: I think the picture explain it. Spudfiles pictures don't work for me though, so I can't tell if it uploaded properly.

nope... try again, or use a website like imageshack.us

I posted some of the frames, hope it helps.

i like the thought process and over-all design. i would recommend a much bigger hole on that barrel that lets air into it
edit:
i think it would be hard to make it air tight but able to slide easily (which is what i think you want)

I like it! But that's gonna be pretty complex. Good luck!

The only 2 problems I see with it are related to the number of seals that design requires. They will all have to be good seals, kept clean (difficult with the sliding chamber on the barrel), and lubricated for low friction. Getting all the o rings sealed, leak free, and not stuck will be difficult.

The port into the barrel will require a double set of o rings for that port to pass through, otherwise the air will burp past the o ring (into and out of the barrel) as the port slides under a single ring. A double ring so the port has to pass through a small isolation chamber on the way in will prevent this burp of air pressure.

Unless you are really good at working with o rings, I would not attempt this. Even with my level of construction, I don't think I could make it workable due to the mechanical seals required.

If you build it and get it to work, you will have shown yourself to be a master builder. Adding a hopper so it would auto load a round into the barrel would make it full semi auto.

so many seal, I've designed quite a few valves and I can tell that this design is not optimized, for the very simple function it accomplishes there are definitely more o-ring seals than necessary.
if you want that revolver style hammer action look into hammer valves

It seems overly complicated... and it's not that you gain something (good performance etc.) for that

It is semi/full auto.

well if our willing to put in the time and money into making your design go ahead.



if you want a semi/full auto use a blowgun or a horn valve from a an 18 wheeler ( i believe horn valves open relitivly fast, get good flow and close the moment ou let go of the handle)

I am not saying it is a bad design... but it is overly complicated and difficult to build...

consider using some off the-shelf-parts (for example the 3 way valve and the air cylinder)
It might also be a good idea to place the air cylinder inline with the barrel


There is even a simpler design that requires only a 3 way, air cylinder and a QDV valve to operate... and essentially is the same as this one.... lol I wonder if technician knows what I am talking about

Xerxys wrote:It is semi/full auto.

I don't understand, how do you operate it in semi automatic versus fully automatic

POLAND_SPUD wrote: ... lol I wonder if technician knows what I am talking about

Yes.. Finishing the 2.5 inch first. Lots of future plans are drawn. Air cylinder will operate off the chamber pressure, a pop off, regulator, etc for full auto. Have plans for it in a golf ball cannon.