Page 1 of 2

Autonomous hybrid caliber .25 Prototype 3

Posted: Wed Nov 28, 2018 1:47 pm
by hectmarr
This is my new project, almost finished. I need to paint it. I have not used
wood, just a little bit, in the grip where the piezoelectric goes because I thought it was nice that everything is in sight.
It is the simplest, easiest and fastest gas dosing system to build,
and it does not fail. :D
The weapon is an autonomous hybrid that shoots steel balls of 1/4 ", to 8X.
The air pump has been optimized to achieve that pressure, without much force,
with 7 pumps. The tube of the air pump has a diameter of 27 mm. The two valves
of the air pump are commercial, and support, according to the manufacturer, up to 10 bar.
The two valves of the combustion chamber are manufactured by me, and
They work very well for combustion pressures.
The firing pipe is smooth bore, built by me. It has a thin steel tube outside,
with polyester resin inside, to give the caliber of 6.35 mm.
It is light, only 1.9 kg.
I have incorporated a very effective silencer, because the noise no longer bothers me.
It is built with an aluminum tube, i have glass wool inside,
to decrease the acoustic energy of the gases.
The fuel gas tank is a simple and common small aerosol, and I use the valve
that comes incorporated from the factory, to inject gas into the dispenser.
The gas dispenser is only a plastic tube of 10 cm3 capacity, which is the
that burns this weapon. It has no piston, and is not subjected to any pressure. The gas when entering
by "A", it dislodges the air by "B", and the gas that remains inside, is then sucked
by the suction valve of the air pump, "C", and introduced into the combustion chamber.
Simple and without failures, for this type of volumetric meter for small arms.
The combustion chamber has a single hard spring, which is responsible for retaining the pressure
of mixing, and leaving the camera with zero volume after shooting, to clean it completely.
I'm using 8X, but the system can hold mix up to 12X without opening the hole
gas exhauster. The problem is that it is not safe to reach so much, because the thickness of the steel tube
recycled from a shock absorber that I am using, only 0.8 mm. I have steel tubes with burnished
inside, but this one in the Mr. of the winch, delayed there.
The red color command seen in the fifth photo is the valve to depressurise the combustion chamber after the shot. Frequently there is some burnt gas inside and it is necessary to press to completely clean the combustion chamber of burnt gases.
When I make the shooting test video, I'll cast it here. This is a totally homemade weapon,
I mean manufactured with few common things, and without any lathe, or welding. I have already fired some
80 times, and everything is still in place. We'll see how it works with more shots. :)

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Fri Nov 30, 2018 7:24 am
by jackssmirkingrevenge
Excellent, looking forward to the videos!

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sun Dec 02, 2018 9:52 pm
by hectmarr
I have thought about cutting the lever because it is uncomfortable to be longer than the firing barrel. I tried and needed a lot more strength, and it would be difficult to pump when I tried higher pressure. The solution was to incorporate a lever that extends and retracts. The painting has improved it a lot, always within its classic appearance of homemade invention. This is how it looks in the present: :D

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sun Dec 02, 2018 10:12 pm
by jackssmirkingrevenge
Looking good!
hectmarr wrote:I tried and needed a lot more strength, and it would be difficult to pump when I tried higher pressure. The solution was to incorporate a lever that extends and retracts.
The solution for quicker shots would be a pre-pressurized air chamber, or better still, a main chamber with a premixed air/fuel mixture under pressure. The danger there of course is that you effectively have a potential bomb as a chamber, although you could mitigate the issue with multiple safety devices like check valves etc.

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sun Dec 02, 2018 11:05 pm
by hectmarr
Yes, indeed, I have considered this option. The truth, although cowardly, I dare not ... To have a tank with a butane-air mixture in stoichiometric ratio at about 15 bar, because I need air for several shots, would be to facilitate everything and a lot, and also a suicide. :shock: Definitely not an option for me, and I hope for no one.
I am satisfied, in this present project, to have something similar to a multiple pumping rifle, like the Crosman Powermaster 66 or similar but more powerful weapons, in fact mine is.
Apart I'm putting together a system of cartridges, such as the autonomous hybrid 1, a test weapon to repeat, with a tank of compressed air, you just have to move the bolt, to eject the ammunition, and return it to the starting position to load the cartridge with the ammunition and the rupture disk and the mixture. It is a simple construction and just today, it worked correctly for the first time. I'll upload the photos and data, when it's finished.
Actually I'm planning the improvised, and improvising what's planned! :)

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Fri Dec 07, 2018 11:24 am
by hectmarr
I leave this information here for the moment. When I have everything in order and concluded I will make a new post to give clarity to my projects.
Automatic mixing dosing system for hybrid weapon

This system is the one that I am considering using to feed my
small hybrids without air pump, with compressed air tank. It works very well already,
I'm just waiting for it to arrive, a solenoid valve that I do not have. It's quite compact.
Use a 5/2 solenoid valve 12 vol and a 3/2 solenoid valve 12 vol.
I have used two 5/2 because they are less expensive and easy to get by these sides.
I think the diagram explains how it works. If someone who is interested,
Have any questions, hageme know to clarify.
The two valves are activated and deactivated at the same time. It has an electrical contact, (push),
in the bolt handle where the ammunition goes. When the hybrid cartridge is inserted,
and you move the lock to close it, the two valves are activated for 1.5 seconds, which
This is what it takes to introduce the pressure mixture into the combustion chamber. This weather
it is controlled and regulated, with electrolytic capacitors that provide energy
to solenoid for this time, once the bolt button has been disconnected.
Just load the cartridge, (which includes the rupture disk and ammunition), and fire.
The green hose is what you have to add to the amount of butane gas
which delivers the dispenser, which is adjustable, to adjust the mixture in the installation of the weapon.
I will update in the future.
That's how it's going to be ... I have to replace the three-way valve that is visible and to the right of the photo, by the solenoid valve.

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sat Dec 22, 2018 3:25 pm
by hectmarr
A couple of shots, where you can see the operation of this simple weapon, without a doubt my favorite system, :) which I will continue to develop in the future time. The dosing system was simplified to the maximum. This aspect is completely solved for hybrid weapons with air pump.
[youtube][/youtube]

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Mon Dec 24, 2018 9:44 am
by jackssmirkingrevenge
I know I keep saying this but eres un fenomeno Hector!

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Mon Dec 24, 2018 11:53 am
by hectmarr
Thanks Jack for the praise, I value it very much. It only remains to give more pressure, increase the caliber to increase power. Time to time, because the head goes much faster than the hands! :shock:
Have a happy holiday I wish you a heart! :bounce: :bounce: :bounce: :bounce: :bounce: :bounce: :bounce:

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Fri Feb 15, 2019 5:15 pm
by hectmarr
Update of today's prototype.
I have included a hold with an o`ring. The strength has increased considerably. He passed a 0.8 mm steel plate cleanly with 7X, and the noise has been kept controlled with the muffler I have installed. I have fired without the moderator, but it is very unbearable for my ears. It was just to know.
In the photos, the red mark is mine, 6.35 mm, the other one is a 5.5 mm pcp.

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sat Feb 16, 2019 7:40 am
by jackssmirkingrevenge
Fantastic result! It's good to hear that you are taking a more academic approach to your development, but stay safe ;)

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sat Feb 16, 2019 8:08 am
by hectmarr
Yes, safety is a priority.
I have to get o'ring for high temperature, viton or silicone. :roll: Those that I use in the present are common, those of black color. I can replace them if they deteriorate but the longer they last, the better.

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sat Feb 16, 2019 11:26 pm
by Potato Demon
If the end of your barrel is threaded, use an adapter and install an oil filter suppressor. Trust me, if they work on firearms, they’ll work on this. Just be sure to drill a hole in the end in case it doesn’t shoot through it.

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sat Feb 16, 2019 11:44 pm
by hectmarr
Potato Demon wrote:If the end of your barrel is threaded, use an adapter and install an oil filter suppressor. Trust me, if they work on firearms, they’ll work on this. Just be sure to drill a hole in the end in case it doesn’t shoot through it.
The weapon has no threads except in the internal retention system. The gun has a suppressor and the sound has been greatly reduced, thankfully :bounce:

Re: Autonomous hybrid caliber .25 Prototype 3

Posted: Sat Mar 16, 2019 12:23 am
by hectmarr
This is the new two-stage air pump with power lever, which I'm building for my next stand-alone hybrid prototype 4.
It has a volume ratio of 2: 1. It allows me to decrease to 3 or 4 pumps to obtain a pressure of about 9 or 10 bar, without it being too hard to handle. I am building it in the present and I hope it works correctly.
The priority is that the pump is as compact as possible, and that I deliver about 150 - 200 ml of air at about 9 bar, and that the pumps are executed with the least possible force and the least amount possible. Actually with the HA 3 after shooting 20 or 30 times, my arm is left hurting ... :| This is, I hope it is really like that, the solution for all this. :)