SpudFiles

I got around to making an animation of my hopefully finalized design that I will be building when I get enough money. The animation does not show the ignition source, so what it is going to be is a Flyback Transformer from a plasma ball. It will be hooked up to two 9v batteries with a momentary switch. The switch will be placed behind the bolt so when it is fully extended, it will be pushing the momentary switch.

As for the long trigger pull, I will have a trigger similar to a pressure washer handle. A pulley system will connect the bolt to the bottom of the pressure washer like handle.

And here it is:

Correct me if i'm wrong, but the burst of propane is the only thing returning the piston assembly? I don't think that would be enough. I'm not much of a combustion expert though.

And another thing, are o-rings fine under such temperatures?

Thanks for the quick reply! The bolt first moves back under the force of your finger pulling the trigger until it hits the ignition. The combustion occurs shooting the BB, then what returns the bolt is a tension spring the pulls it back forward. (forgot to mention the bolt spring )

As for the o-rings, I might have to get high temp. rubber o-rings or something if my cooling system doesn't work well enough. I think I will make a water tank made out of rubber reducing couplers and 1.5" ABS surrounding the combustion chamber to cool it. I could have a screw-on cap to pour the water in and then say to my friends that my gun runs on water!

Something like this:

That animation looks very familiar.....

Yes, it is based off of the Tippmann C3. This design is a modification of a previous design I made: http://www.spudfiles.com/forums/inline- ... 16481.html

except this design incorporates a spool valve metering system and is in an awesome animation format.

Great design.
I noticed it has two valves similar to an engine. Except in an engine one valve performs both functions (fuel air mixture) and the other valve exhaust.
Looks like it will exhaust through the back somehow. (one way on the piston or...?)
If it only exhausts out the barrel, seems like the inert burnt gases would eventually reach (at) the pressure needed to open the blow forward bolt spring. Getting in the way of fresh fuel/ air entering. (?confusing...)

Also for a design similar I'm wondereing if a pull Back bolt would work better. As the chamber piston moves rearward it could pull the sleeve back with it, loading the barrel and blocking the loading port.
That would eliminate stress on the bolt as it blows forward. (By loading rearward it needs no further movement when fired). (Hmmm...?)

Also perhaps a design similar to the piston rings of a combustion engine would work better than rubber o-rings. 8)
Looks nice though!

EDIT: I really see no need for having two main moving parts instead of one (The piston and the blow forward bolt).
Seems like a larger blow forward bolt rear, and the air/ fuel pressure could move it forward, through a one way or check valve (constant pressure).
Just before opening the bolt, a switch would make contact igniting the mix and opening the bolt fully (if the trigger switch is also pressed).
So It seems a little overly-complicated IMO.
Perhaps a lever inside or on the trigger could open a valve temporarily for exhaust venting also. 8)

My design does not utilize any combustion power to move the piston/bolt. The only thing moving it is your finger (trigger) and a return spring (which isn't shown).

I believe what you are talking about may be something along the lines of how the Tippmann Propane hammer works (an automatic propane combustion design that I thought about utilizing in an airsoft design, but wouldn't work because of lack of supplies) This design uses the momentum of the piston and combustion to make a complete cycle. (I don't think that momentum could be used in an airsoft design because of a naturally light piston and sideways function.) Here is further information about this stake pounder on a thread a made http://www.spudfiles.com/forums/semi-au ... 16379.html (go to the bottom of the page)