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Posted: Tue Nov 08, 2011 4:07 am
by jean
nobody here to help me and to discuss my diagram?

i see the minigun but it is another concept...

forget the building issue and forget the fuel meter!


let see what the cylinders do...

please help me to figure it out please

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Posted: Tue Nov 08, 2011 4:13 am
by jackssmirkingrevenge
this is the cycle you need, apart from reloading the projectile (this can be done separately using a blowback/blowforward bolt) is as follows:

1)make sure there is fresh air in the chamber
2)inject correct amount of fuel
3)ignition

and repeat...

Posted: Tue Nov 08, 2011 4:35 am
by jean
the right part of the diagram works pretty good also the reloading.
i had test it but with syringe fueling and in a getto assembling

and the repeating process will done through the cylinder?
have it the ability to recock itself?.

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edit
my big fear are the many leaks they come up in the process of going forward.
or make with o-rings but this is maybe to much friction......

Posted: Tue Nov 08, 2011 9:02 am
by wyz2285
With floating o-rings, the friction may not be much, but a combustion is weak in a airsoft scale, and in your design a high volume of expanding gas are wasted to the recycling process. How are you going to make sure there are enough fresh air in the chamber to have a combustion reaction? Assuming you want a decent rpm.

Posted: Tue Nov 08, 2011 9:11 am
by Gun Freak
I see no use in further discussion or improvements of this design... It's way too impractical.

Posted: Tue Nov 08, 2011 9:17 am
by wyz2285
Agree, that's the first thought I had when I saw this design, pneumatic it's way easier for the same goal.

Posted: Tue Nov 08, 2011 9:24 am
by Gun Freak
THAT'S ALL I'M SAYING. :D

Posted: Tue Nov 08, 2011 10:54 am
by jackssmirkingrevenge
I hate agree with GF but I don't see this happening without some sort of external mechanism cycling the action, the forces and inertia involved and the brief interval in which the various chambers will be pressurised is insufficient in my view to make it work.

I would go for cartridges...

Posted: Tue Nov 08, 2011 11:51 am
by wyz2285
I would go for cartridges...
We all know you are going for cartridges jack :roll: even through this design may not work, but for automatic combustion/hybrid, there are other ways, nothing wrong at all if some people try to go for that way. For me is PNEUMATIC :D .

Posted: Tue Nov 08, 2011 4:57 pm
by Gun Freak
For me is PNEUMATIC
That's ma boy!!! :D

Posted: Tue Nov 08, 2011 6:39 pm
by jean
jackssmirkingrevenge wrote:........I don't see this happening without some sort of external mechanism cycling the action, the forces and inertia involved and the brief interval in which the various chambers will be pressurised is insufficient in my view to make it work.
can you explain it please .. it is difficult to understand for me .. my english.....

ok my goal is a full-auto combustion without any other power than the combustion out of the fuel. no bulky regulators or dcv or something other stress ) and please no torch thingy fuel.

what option's i have?
because of the fast rate of fire i have in my mind (say 3 per second) i think a piston that displace the combustion gas and suck new fuel in is the right way (like a car motor)
but how to driven it??

any suggestion?


without the word's minigun, pneumatic or cartridge :D thanks

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Posted: Tue Nov 08, 2011 10:54 pm
by jackssmirkingrevenge
jean wrote:ok my goal is a full-auto combustion without any other power than the combustion out of the fuel. no bulky regulators or dcv or something other stress ) and please no torch thingy fuel.

what option's i have?
You realise this is something that has never been built, so it is certainly an ambitious project.

In your design, you want the barrel to move forward while there is still pressure in the chamber, the forces will cancel eachother out and it will stay still.

Rather than using a "moving wall" suppressor to cycle the action (works great in the FX Monsoon at 1500-3000 psi, but a 100 psi combustion, hmmm...) I think you should try and use the substantial recoil forces as the agent by which to vent the chamber and refuel.

I also think you should separate the action of reloading the projectile from refuelling. There are plenty of systems (such as theblow forward bolt) that can use the propelling gas to do that separately.

Posted: Wed Nov 09, 2011 2:29 am
by POLAND_SPUD
ok my goal is a full-auto combustion without any other power than the combustion out of the fuel. no bulky regulators or dcv or something other stress ) and please no torch thingy fuel.
You do know that a car engine has valves in it and a sort of regulator (carbourator)?

You're saying I want to build a wheel that's rectangular and doesn't move

Let just say I know what you mean but if you don't include off the shelf parts in your design you have to build them your self and include them in the design.... that makes things a lot more difficult

Posted: Wed Nov 09, 2011 3:14 am
by jackssmirkingrevenge
POLAND_SPUD wrote:You're saying I want to build a wheel that's rectangular and doesn't move

Let just say I know what you mean
Says it all really :D

Posted: Wed Nov 09, 2011 6:21 am
by The Hellforger
Yeah everything else aside, your absolute biggest problem and its one that will stop this auto combustion dead in its tracks) is venting the chambers. The way your diagram is laid out you have very little in the way of bringing fresh air in.

After we solve the problem of the oxidizer we need to deal with heat. Your going to generate ungodly amounts of heat.

Basically you have an overthought out shocker (paintball gun). If tippmann can design a pump action combustion marker but can't or won't build a semi-auto combustion it is probably for a good reason