i got up with a idea on a semi combustion.
you have four chambers fueled and ready to fire connected to a cross via a burst disk. you have four chambers and one barrel.
you fuel the chambers after you have put in a brust disk and have independent ignition in every chamber. you fires one chamber, the golf ball goes, then another ball falls in the barrel from a magazine and you fires the other chamber, and repeat.
i don't mind explain and make diagrams before i know somebody are willing to try it.
front sides: high rate of fire.
back sides: slow reloading, dead volume and building time and prise.
semi combustion
Sounds pretty awesome! I understand completely but a diagram would be nice 
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mark.f
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Me and my friend were talking about semi-automatic combustions yesterday whilst collecting (wet) firewood.
The way he was approaching the problem was first to step it up to pump action like a C3 paintball marker. He attached a small basketball pump to his chamber via a schrader valve (which I suggested he remove the core from for better airflow), and used that to vent the chamber after each shot. If you could find a way to automate the venting and fuel injection, while having a continuously running mixing device, you could have a pump action. Then, a solenoid and electronic firing circuit could be added for semi-automatic fire, much like an autopump paintball marker.
The multiple chamber idea has been utilized before, and I think it's just plain impractical. Why waste all that money on multiple chambers when a bit of homemade electronics, duct tape, sweat, and ingenuity can get the same thing out of one?
Oh, and also, if you remember noname's hybrid... he used a small tank of compressed fuel air mixture that he filled his hybrid with. With a bit of 555/6-timer wizardry, some solenoid valves, and some calculus, you could make a circuit that injected enough fuel-air mixture to displace the combusted remains in the chamber, fill it with f:a, and then trigger the ignition circuit.
The way he was approaching the problem was first to step it up to pump action like a C3 paintball marker. He attached a small basketball pump to his chamber via a schrader valve (which I suggested he remove the core from for better airflow), and used that to vent the chamber after each shot. If you could find a way to automate the venting and fuel injection, while having a continuously running mixing device, you could have a pump action. Then, a solenoid and electronic firing circuit could be added for semi-automatic fire, much like an autopump paintball marker.
The multiple chamber idea has been utilized before, and I think it's just plain impractical. Why waste all that money on multiple chambers when a bit of homemade electronics, duct tape, sweat, and ingenuity can get the same thing out of one?
Oh, and also, if you remember noname's hybrid... he used a small tank of compressed fuel air mixture that he filled his hybrid with. With a bit of 555/6-timer wizardry, some solenoid valves, and some calculus, you could make a circuit that injected enough fuel-air mixture to displace the combusted remains in the chamber, fill it with f:a, and then trigger the ignition circuit.
lol, sounds to me like you're just being lazy :sleepy2:spudfarm wrote:yeah and it can be used for hybrids to.
the diagram have to be fairly complicated but if people understand i don't care about it
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I don't think that would technically be semiautomatic, you'd basically just have 4 cannons. Before the Gatling, Maxim, revolver etc. there were volley guns and even pistols with multiple barrels which were essentially multiple firearms in one package. But we don't call those (semi)automatic, do we?
I think the way to achieve higher ROF with a combustion is either quickly venting and filling one chamber or alternating between two chambers (one firing, the other venting and loading) or even three, on the same principle. It is difficult to apply the design of automatic firearms to combustion cannons, since we a re dealing with very different energy densities.
I think the way to achieve higher ROF with a combustion is either quickly venting and filling one chamber or alternating between two chambers (one firing, the other venting and loading) or even three, on the same principle. It is difficult to apply the design of automatic firearms to combustion cannons, since we a re dealing with very different energy densities.
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SpudFarm
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there is one barrel and four chambers
just about the fastest crappyest diagram i have ever made in my entire strange life as a spud gunner dude.
just about the fastest crappyest diagram i have ever made in my entire strange life as a spud gunner dude.
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trollhameran
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that looks like it would work, but could i suggest that instead of having the chambers like they are there, angle them back so that they take up less space and the energy will be moving in a better direction if they are pointing towards the barrel more
How do you know that the other burst disks wont burst too?
Say you ignite chamber 1, the pressure rises to bursting pressure and it bursts. The pressure diverts to the cross and rises even further while pushing the projectile the first inches, and now there is a pressure differential between the cross and the other chambers. Blam, one of the burst disks go off, and if your lucky this chamber also ignites.
This wont happen if you got very good disks with an accurate burst pressure, very high to the pressure peak, and a big dead volume would also do the trick.
I think that with four pvc 2" ballvalves, it would be more practical, since you can close off a fired chamber again and the chambers are better sealed off from the cross.
Say you ignite chamber 1, the pressure rises to bursting pressure and it bursts. The pressure diverts to the cross and rises even further while pushing the projectile the first inches, and now there is a pressure differential between the cross and the other chambers. Blam, one of the burst disks go off, and if your lucky this chamber also ignites.
This wont happen if you got very good disks with an accurate burst pressure, very high to the pressure peak, and a big dead volume would also do the trick.
I think that with four pvc 2" ballvalves, it would be more practical, since you can close off a fired chamber again and the chambers are better sealed off from the cross.
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SpudFarm
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i thought of that but a golf ball don't weight to much to build pressure.
and i did not put elbows in the pic because it would have taken a long time to draw.
and i did not put elbows in the pic because it would have taken a long time to draw.
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rcman50166
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That would be extremely unweildly. You should try to make my design semi auto. The fueling mechanism has already been designed. With some design modifications you probably could make it full auto.
http://www.spudfiles.com/forums/propose ... 12861.html
http://www.spudfiles.com/forums/propose ... 12861.html
