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Posted: Wed Nov 09, 2011 1:05 pm
by POLAND_SPUD
Says it all really
Bastardo !
:wink:

what I was saying was -> you will use DCVs, you just make it harder because you have to build them/design your gun so that it some part of it will function as a 3 way

Posted: Wed Nov 09, 2011 5:30 pm
by jean
ok thanks for your word's and suggestions

i hope your are not sad if i go back to the drawing board because my goal isn't gone.
i hope for help here.

@jsr
yes the barrel have to move wile pressure is in the chamber
but i can't see the forces cancel each other. they are
two cylinders =1+1+(-1) =+1 pressure right?let say the cylinder isn't around the barrel. say the piston-face for the cylinder is double the
piston-face of the chamber-piston.

@POLAND_SPUD
yes i know, maybe this things i can't build. i see the reason.
the fuel meter stay at atmospheric pressure so a reg isn't necessary.
mh i can change it to a dcv fuel meter...but it needs a regulator.

@The Hellforger
yes i'm thinking about seperate the exhaust and inlet.
because the heat: it is ok for me im shooting one magazin say 10 shoots and let it all cool down.
sorry i know the shocker and i googled again but i cant' see the comparability.
your argument if a company haeven't build it- than it isn't worth it- that! is not for me...


ok things to do
1. change the breech and close the leak around the loading cutout duo the change to bfb.
2. serperate the exhaust port and the port for incomeing air.


ok now math
say 80 psi
-headloss/friction say 50%
-the cyliner that is double the volume of the combustion camber -headloss say 50%

80/2=40
40/3=13

say the barrel is 50% of the chamber volume
13/100x75=8

=8 psi

thats 8 psi to push

roughtly i know

by

Posted: Thu Nov 10, 2011 1:05 am
by jackssmirkingrevenge
I guess the way to shut everyone's mouth would be to build it :) again though I would try to use the recoil to cycle the action, as opposed to a gas driven piston, and keep projectile loading separate from the venting/filling cycle.

Posted: Thu Nov 10, 2011 1:21 am
by Lockednloaded
jean wrote:
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

by
Basically what you're asking for is a design similar to an internal combustion engine, but without all of the quintessential doo-hickeys that make it actually work :?

What's your motivation that makes a combustion your only option? There are times for pneumatics (i.e. semi and full auto guns) a time for combustion (large bore high volume single shot guns) and a time for hybrids (when one gets to the point in their spudding career where they can finally grow a pair :lol: ) But you're just reinventing the wheel without using the complications of the necessary parts

Posted: Thu Nov 10, 2011 9:29 am
by The Hellforger
For the shocker comparison, your design is a spool valve design. Its is really a mix of shocker and dm design but primarily for the way it is laid out it falls to the shocker side of the design.

I never said if the company hadn't built it then it wasn't worth it, I said that since they hadn't built it there had to be some reason. I mean tippmann isn't one to shy away from a challenge (after all they are the one and only company in the paintball industry to have a propane fueled, combustion driven marker). And that mArker was getting along the lines of multiple thousands of shots off one small propane tank so if they made it semi it would definitely sell.

The way you've your design laid out physically will not work, especially the way you envision it. As stated earlier, you have inadequate ventilation. Thats gonna stop the gun dead in its tracks. You'll fire round one, the bolt will go forward and send the round down range. Shot two jams up because all the exhaust gases that didn't escape are building up in the chambers. And the cycle will just continue.

I'm not trying to stifle creativity, just stating the truth

Posted: Thu Nov 10, 2011 9:43 am
by The Hellforger
here is how the c3 works.

Image

you pull the trigger to light the spark and ignite the fuel/air mixture. after the paintball is shot you pump the marker back, in doing so the waste exhaust gas is transfered to the other side of the piston. once you begin the return stroke the waste exhaust gases are forced out the front of the gun body in front of the piston while at the same time a fresh fuel/air mix is drawn into the firing chamber so the process can be repeated.

here is a basic animation of a shocker.

Image

your drawings are very similar to that except yours has a poppet valve to controll the inflow of fuel and your bolt sail is larger.

and lastly i will present you with the ion, this is the design that would work best for you (if it was at all possible) for an auto combustion. all that would need to change is that the bolt would need spring return as opposed to air return

Image

Posted: Thu Nov 10, 2011 8:18 pm
by The Hellforger
here is a link to an old thread on pbnation where there was a big play around with ideas for a semi-auto that was propane powered

http://www.pbnation.com/showthread.php? ... +semi+auto

And going back over this thread to make sure i hadn't missed anything, i had a huge epiphany.

Image

the expanding gases in the blue circle counteract the gases in the black circle so it stalls out all your forward moving momentum which puts another nail in this designs coffin

Posted: Thu Nov 10, 2011 8:30 pm
by Gun Freak
Hellforger, I think the gasses push forwards on two faces and back on one face so the net force is actually forwards. I think it was brought up earlier in the thread.

Posted: Thu Nov 10, 2011 8:39 pm
by The Hellforger
thats true forward pressure would drive it forward since there is more of it.

but i kinda picture it as a v8 running with a dead miss, you can do it but you shouldn't and worst case scenario your throwing rods through crankcases

Posted: Thu Nov 10, 2011 8:56 pm
by jackssmirkingrevenge
The Hellforger wrote:thats true forward pressure would drive it forward since there is more of it.
Even so, the gasses are expected to do too many acrobatics in a short space of time, while this looks fair on paper I would be surprised if it worked in practice.

Posted: Thu Nov 10, 2011 8:59 pm
by The Hellforger
yeah it definitely has a lot of work engineered into one moving part. it has a barrel/bolt/hammer(for the poppet) all in one plus anything else i forgot to add