Single pumping hybrid, "Strong Boy"

[jackssmirkingrevenge]

I already have the two simulators on my pc. What is the difference between both programs? Just to know ...

GGDT is for pneumatic launchers, HGDT is for combustion and hybrid type launchers.

[hectmarr]

okay. I tried to install the simulator on my pc, old pc with window 7), and I get 339 error. Apparently a file is missing. I searched the web and found ´comdlg32.ocx´ to download and try to solve the problem.
I leave in the publication on HGDT the video with the link to download, in case someone happens the same.

[hectmarr]

My question is the following. The volume of the uncompressed mixture, in the simulation with a 2 cm diameter chamber, what is it? I mean how much total length should the compression tube have? and how many X is all this ...
Answered in your comment. I did not remember.

 

[jackssmirkingrevenge]

The volume of the uncompressed mixture, in the simulation with a 2 cm diameter chamber, what is it? I mean how much total length should the compression tube have? and how many X is all this

In my simulation I assumed that the length of the chamber tube uncompressed was 20cm.

This means that if we compressed it to 10cm, then the mix is 20/10 = 2 and the chamber length is 10cm.

If we compress to 2cm, then the mix is 20/2 = 10 and the chamber length is 2cm.

[hectmarr]

Yes, it is already clear what I could not see there. Thank you
 

[hectmarr]

I got something but shorter than necessary. I have a 2.1 cm steel tube but the usable length is only 13 cm ... I thought of using 8X with a mixing volume of 45 cm3 and a combustion chamber length of 1.62 cm. The length of the barrel .25 will be 25 cm, (I will make it myself, so it can be of the length that I want).
I'm going to try like this, I can't do much more. It was impossible to buy a seamless steel tube of 1 cm inside diameter, or here there is nowhere. The minimum commercially available is 1 ". The one I have is a motorcycle shock absorber, of good quality and 1 mm thick.
It is clear that the system has interesting possibilities. As Jack showed in his simulation. With a tube of 1 cm in diameter and 25 bar, this hypothetical weapon would fire at more than 600 fps, (with more speed than my co2 gun, which does it at 450 fps), weighs much less, is smaller and simpler . This without trying to compare two very different things, but I think the energy of unarma like this is interesting. I differentiate well what I can build from what design can potentially give.
There is the possibility of using a simple rupture disk, without a doubt, and of using more pressure. Apart, with 25 kg of applied force, (can be achieved), the weapon shoots at 32X.
This are the dimensions of the weapon. With a cigarette lighter, it is enough to feed it. With those who have a small built-in valve, to recharge butane. The dispenser is a piece of hose 6 mm inside diameter, 8 cm long. The butane feed group is reduced to a small size.

[jackssmirkingrevenge]

Looks good!

I had similar dreams some years ago, the difference is that you are actually making them reality! Respect.

[hectmarr]

I am reviewing the design of your drawing, which you had seen before, to understand well.
For my part, I have to redo everything because it doesn't convince me how the work was. I do not think it is safe to use the photos, because the forces involved when exploding are about 150 to 200 kg, approximately, in the lock of the bolt, (3.46 cm2 x 50 bar). I don't think I can stand ... I have to look for a longer tube. To this attempt I will use it in the bank, not in my hands, and no more than 4x.
From what I could prove, it is possible to reach 8X perfectly, in 2.1 cm of piston diameter. The bb that is the ammunition and the inlet valve of the mixture, works perfectly, and does not let out any air at all. When the piston is pulled, the ball runs a few milliliters and lets air through. It has a neodymium magnet to stay soft and normally closed.
As my friend would say, good try and redo everything again.
I think the "new" here is to achieve decent pressure, otherwise it is very simple and common. Try to make a video of the prototype with a built-in manometer, so you can see the stage you get compressed.
 

[jackssmirkingrevenge]

For my part, I have to redo everything because it doesn't convince me how the work was. I do not think it is safe to use the photos, because the forces involved when exploding are about 150 to 200 kg, approximately, in the lock of the bolt

That is like an average American adult is standing on it! Stay safe!

Try to make a video of the prototype with a built-in manometer, so you can see the stage you get compressed.

Good idea, but don't forget to put a safety valve you can close before firing, otherwise your gauge becomes "uso unico"
 

[hectmarr]

oh yes of course, the manometers are more or less decent.
Today I won a chess game to the damn experiment, I was playing with him all afternoon!
I managed to shoot several times, using as a dispenser, only the firing gun that is in 7 cm. Everything worked perfectly, and with a lot of noise. I am using a cigarette lighter as a reservoir, which must provide the 2 cm3 of butane necessary for combustion. In hybrid it is loading about 40 cm3 of air. I added a bronze tube to the gun to increase the volume of the combustion chamber and to lower the pressure to about 3 - 3.5 bar.
It happens that when I install the pressure gauge to measure what pressure is being compressed, the small hose of the pressure gauge plus the volume of Bourdon tube that the pressure gauge has, lowers the pressure a bit. Heisenberg's "uncertainty principle" applies here, because the measurement varies the results hahahahahaha
I think I'm going for a more powerful prototype, after sniffing the difficulties inherent in the design. I will do it when I get a longer steel tube.
My idea is that with a little more air, about 100 cm3 and about 8 or 9 bar, it will be a good power gun, simple.
I will upload a video to illustrate the experiment. 8)
This is what I am testing, in its simplest version, (which is what interests me).
The ammo moves to the right when the piston aspirates, and aspirates the dose of butane and air. When the piston compresses, the ammunition bb blocks the combustion chamber and the mixture is compressed.

[hectmarr]

This is the "S.B 1", which I am using to test.
It works well, but by adding the bronze tube to increase the volume of the combustion chamber to be able to operate it at less pressure than planned, it surely loses energy through the dead space.
I am using .25 caliber, a common lighter, and everything is built without using resin, (except in the ignition, to avoid air leaks).
These are some pictures of how it looks 8)

[jackssmirkingrevenge]

How are you controlling the dosing of butane?

[hectmarr]

How are you controlling the dosing of butane?

The firing barrel has the necessary volume. When the butane lighter is pressed, the gas enters and displaces the air, leaving 2.2 cm3 of butane. When moving the piston to the right, in the drawing, it is sucked along with the air. Logically, after loading the gas into the barrel, it must immediately be sucked into the weapon. There may be the time you want, and only the weapon is compressed before firing. It's simple to add a manual ammunition charging system, but I'm interested in trying the design basically. It is the only autonomous mono pumping hybrid that I have hahahaha
It actually conditions the length of the barrel, but I needed to try, and it works without failures. In appearance, the prototype has no dispenser.
I am struck by the very loud noise it produces, (I shoot it with earplugs), with so little air, no more than 40 45 cm3.
It feels strange to shoot with just the ammunition in my pocket, I like that. I am adding a handle that has the piezoelectric and the butane lighter. It has proven safe to use on the hand at low X,

[jackssmirkingrevenge]

Ah I get it, and the projectile acts as a check valve. Very clever!

It is the only autonomous mono pumping hybrid that I have hahahaha

I think it's safe to say that it's the only single stroke self contained hybrid that anyone has!

I am struck by the very loud noise it produces, (I shoot it with earplugs), with so little air, no more than 40 45 cm3.

I would surmise that this is due to the extremely small barrel volume, leaving not a lot of room for gasses to expand and lose pressure before they exit the muzzle.

[hectmarr]

I would surmise that this is due to the extremely small barrel volume, leaving not a lot of room for gasses to expand and lose pressure before they exit the muzzle.

Indeed, the barrel is very small, limited by its double barrel function, and gas dispenser. I think that variant 2, which sucks the mixture into the combustion chamber, releases the barrel from its double function, but has a very small external dosing, and an auxiliary check valve. The ammunition bb, no longer lets anything happen to the camera. The admission is made through a side port connected directly to the combustion chamber.
This option 2 is as in the drawing: