An hypothesis for a lighter, more efficient air system than HPA.

[snoopay700]

Hello I am very surprised at this thread because I am currently attempting to design a semi automatic propane powered paintball gun. I am just starting to scratch the surface here, but I have found many ways to deal with the heat issue. My only problem is finding a way to add oxygen to the propane mixture without using an air tank.

I am currently studying the mechanics of this to help me think of a solution.
Basically, if I could find a way to use the excess combustion to cycle the gun for the next shot like the AK-47 then I would eliminate the need to use compressed air or CO2.



advantages of propane:

1. Consistency
2. Efficiency 5000 + shots
3. Cheap
4. Safe. propane tank is only 150 psi. Compressed air tank is 3000 or 4500 psi.


Disadvantages of propane:

1. Generates heat (possible solutions found)
2. Requires oxygen to work ( researching)

Nah, something like that wouldn't work well, you'd be better off with a sort of poppet design most likely, you ignite the propane in the chamber as the hammer is traveling toward the poppet, it fires, and then the excess gas pushes it back, a sort of variation on the STBB design. Everything would require a new specific board to operate most likely, but it could work. Another idea is a sort of Mini-ish idea, but with all of these heat would be an issue unless you made the body of the marker into a heat sink, and i have a feeling that design wouldn't be very popular.

[RavishingEddie]

Nah, something like that wouldn't work well, you'd be better off with a sort of poppet design most likely, you ignite the propane in the chamber as the hammer is traveling toward the poppet, it fires, and then the excess gas pushes it back, a sort of variation on the STBB design. Everything would require a new specific board to operate most likely, but it could work. Another idea is a sort of Mini-ish idea, but with all of these heat would be an issue unless you made the body of the marker into a heat sink, and i have a feeling that design wouldn't be very popular.

What if I found a way to use anti freeze inside the gun? Would that work?

[snoopay700]

What if I found a way to use anti freeze inside the gun? Would that work?

It would need to run through a heatsink aka radiator, I've been thinking about a way to cool it with liquid and it would just make it heavier because of the need for some kind of radiator, and truthfully the heatsink idea is easier and lighter, though i don't know how effective it would be. Actually i have an idea i think would be really good and would work, but the heat is the main problem, but other than that it would work and would be pretty small.

[snoopay700]

I just realized, heat isn't the biggest obstacle to overcome with a propane powered marker, it's getting the exhaust gasses out and the air in. That's why the C3 is a pump now that i remember, and it wouldn't be as simple as the design i have, it would work but it would eventually choke itself. I could probably find a way to purge the chamber between shots, but it would be tough.

[RavishingEddie]

I just realized, heat isn't the biggest obstacle to overcome with a propane powered marker, it's getting the exhaust gasses out and the air in. That's why the C3 is a pump now that i remember, and it wouldn't be as simple as the design i have, it would work but it would eventually choke itself. I could probably find a way to purge the chamber between shots, but it would be tough.

Yeah that is my main obstacle right now. It isn't like striking a bullet with a pin. You have to combine gas,air and igniter. I was thinking of creating an opening in the body to expose the bolt and everytime it would cycle, the bolt would open and close catching air and cooling in the same time. I would really like to come up with a way to not use electronics.

[Hilltop Customs]

Air isnt really a problem, just need to design a pump into the marker. Need 2 check valves and a piston with a cycling movement. Bolt movement could be used as they piston pump(either by directly designing the back surface to be used as the pump or used to actuate the piston). One check valve only allows air to enter(from the outside) the piston stroke area, and the other only allows air to leave the piston stroke area(compressed out by the piston into the combustion area.

timing the inlet and exhaust of the combustion area(opening and closing of ports as the bolt moves) could be used like a 2 stoke engine to accomplish the removal of exhaust gas and inlet of fresh air and fuel. Since the air is pressurized by the piston, and the propane is pressurized out of the bottle a 2 stroke engine design is possible.(no need for crankcase pressure).

essentially design a 2 stroke engine which only fires when you pull a trigger, and you have a paintball marker that uses propane as fuel.

edit:
by 2 stroke which only "fires"; I meant a single stroke for each pull of the trigger.

No matter what it is not going to be fun to design for...considering the large heat increase of high rof will reek havoc of shot to shot velocity between strings and single shot. Depending on the design, you may even have to go with some sort of dwell compensation to account for the large heat increase you could possibly get with long strings. Also consider the fact that, if you have a controlled combustion, then release the "exhaust" down the barrel, any deviation in timing between those two events could lead to massive swings in velocity.

IDK if thats what you guys were thinking of or something similar to a bullet where combustion will be happening directly behing the projectile(paintball) itself. In that case you will still have to worry about the sequence of events leading up to firing....is the gas held in a chamber that will possibly heat up during high rof? if the chamber becomes hot, then gas is held in it for a short time, the gases will heat up, and then combustion will occur at a faster rate than room temp gasses.(meaning faster acceleration and higher velocity). It might not be much of a difference, more of something to look out for.

[Ruler_Mark]

MR. Hal B.



Make it and we shall see.

[snoopay700]

Yeah that is my main obstacle right now. It isn't like striking a bullet with a pin. You have to combine gas,air and igniter. I was thinking of creating an opening in the body to expose the bolt and everytime it would cycle, the bolt would open and close catching air and cooling in the same time. I would really like to come up with a way to not use electronics.

You need electronics unless you use a match to fire it, because the arc is what ignites the propane, why else did you think heat was a possible issue?

[ghtpDM5]

well, looking at this as i see it right now, the winchester sx series shotguns, or near any gas reloaded shotgun on the market(the sx series some to mind for efficiency in the system) could provide a good base for design, replace the exhaust chamber with a combustion camber and you may damn near have it, the only thing is getting the fuel injection system reliable(be it mechanical of electronic, my preference being the mechanical) this could be done, but the issues to be dealt with aren't worth the cost to me

[halB]

What if I found a way to use anti freeze inside the gun? Would that work?

Antifreeze would accomplish the very thing i am talking about: absorbing energy. However, CO2 would do it a lot more efficiently and compactly (although it would be a resource that is used up) because it goes through a phase change - just like air conditioning. I just wouldn't bother pumping it back into a liquid...

or... would there be enough excess energy from the propane explosion TO convert it back into a liquid...

but then, you'd just be moving the heat to another part of the gun. So I guess exhausting the used CO2 would be the best decision.

edit: It would be two tanks, the CO2 would never be combined with the propane.

[Chris Nearchos]

why not

why not forget about the whole tank system? and just come up with a tiny high OR low pressure ultra quick air compressor unit? about the size of a classic valve?


something along the lines the idea of a turbine engine using magnets to power it or a battery.


just an idea that doesnt have to deal with deadly gas.

-Chris

[Hilltop Customs]

you will lose efficiency with every step in the system. So including compressing a gas in the marker will result in requiring more energy stored in battery form than what is stored in compressed air for the same number of shots.

what I mean by this is easier to have that loss occur at a large compressor that is ran off the power grid, than have that loss drain a battery which has to be carried around.



that and you will also need to create a method of compression which needs to be small, quiet, and efficient.....which wouldnt be easy.

[halB]

why not forget about the whole tank system? and just come up with a tiny high OR low pressure ultra quick air compressor unit? about the size of a classic valve?


something along the lines the idea of a turbine engine using magnets to power it or a battery.


just an idea that doesnt have to deal with deadly gas.

-Chris

One day there will be paintball guns powered by either awesome capacitors or via hydrogen. But, not today.

We need to find the next step before we get the amazing paintball gun that doesn't need a tank.

[Chris Nearchos]

that and you will also need to create a method of compression which needs to be small, quiet, and efficient.....which wouldnt be easy.

didn't say it would be easy...just another idea. and as for a loss of energy in the system (aka waste), just gotta find a way to make it efficient. and with battery efficiency getting much better with the new batteries being developed....wouldnt have much of a problem with powering.


but on the other hand, its not any harder of an idea then using an explosive gas to power the marker (or even a gun in general). Governments have been trying to overcome the whole heat issue since rapid firing became a reality with firearms.

just thinking outside the box.

-Chris

[Chris Nearchos]

One day there will be paintball guns powered by either awesome capacitors

didnt even think about that. but then that would require some kind of big battery pack. probably a backpack to start out with.

i think i might have to explore this idea further.

-Chris


**Edit**

as for finding a step inbetween comment, let me ask you this. why convert from one gas to another when in the end, your gonna be needing more to make a marker function then what you did with in the begining? while in the process making it more dangerous for people to use?

not trying to kill your idea, just wanted to ask that.