New JSR semi-auto prototype (split topic)

[jackssmirkingrevenge]

JSR- here is what I PMed you about

Interesting, looks like a combination between this valve and the pop-off auto valve. I'm sure it could be made to work, but I'm not sure if it would be practical compared to other solutions. There would certainly be issues with sealing, I would think that replacing the air bumper with a coil spring would make things easier. For full auto balancing the flow rate and the spring would also be a bit of a chore.

Well jack, how's your prototyping going?
Any pictures of the progress?

Well, I've decided to make it. Still bothered by the limited flow concerns mentioned previously but we'll see, I might make a 3mm semi-auto pistol

Here's the bits before I epoxy them together, it's basically a very short pengun with a spring behind the piston and holes in the chamber

[POLAND_SPUD]

well I know it's not a good idea to post your own stuff but I think that -> this might be better

I didn't have time to test it properly but it could waste no air when used as the main valve (but it can be used to pilot a QEV) and it could be used with air cylinders

I think that the design can acheive what jsr always wanted to achieve, that to build an efficient valve that could be controlled/triggered with just one valve...

but IMO personal he shouldn't care that much about reducing wasted volume to zero as it isn't something that can't be fixed by using a slightly larger HPA/CO2 tank.. there are other things out there which are much more important and which could be improved

EDIT

though, now that I think of it his design ( the one that he created earlier - you know the one that is similar to you design) functions more less in the same way as mine...

the only difference is that mine can be tuned via a throttle valve (flow restricting valve) as it has separate 'ports' for piloting (switching by means of pressurising) the valve and exhausting the chamebr (barrel port)... IDK if you can visualise what I mean but they are indeed quite similar... hmm it does feel strange when you see that everything is just a modification of something that was done in the past

[Brian the brain]

it doesn't make sense to have an autoloader that still has to have its hammer manually cocked for every shot.

With the forced blowback system, the bolt could reset the hammer.
Basically like in a Colt 1911 style.

Oh and I was messing with yall.
I know I'm the greatest....

You guys should realise that eventhough I'm sober all the time..this is not true for my sense of humour.

Jack, I wish you the best of luck, eventhough I have seen you embark this sort of hunt for prototype after prototype in the quest for pressure activated full auto for quite a few years now.
Meanwhile I bought a 1/4" qev, Psy is lathing me a new Snapvalve and I'm thinking up my own version of the forced blowback bullpup.
The blowback-hammer version will come after that.
I hope to create a very silent one this time so I can actually enjoy it.

With my latest buy, being two divingbottles, I don't really care about lost pilot volume.

[POLAND_SPUD]

being two divingbottles

how much for them? care to post more details ?? how much for the shipping ?

I am going to buy something similar soon

[jackssmirkingrevenge]

but IMO personal he shouldn't care that much about reducing wasted volume to zero as it isn't something that can't be fixed by using a slightly larger HPA/CO2 tank.. there are other things out there which are much more important and which could be improved

Fair comments...

Jack, I wish you the best of luck, even though I have seen you embark this sort of hunt for prototype after prototype in the quest for pressure activated full auto for quite a few years now.

Well this is a bit different, it's an attempt at creating an actual finished pistol type launcher, I'm aiming for semi-auto here but with a lever trigger instead of a hammer, you could conceivably achieve a flow as opposed to a burst of air, with a tee breech this means burst fire is possible.

Meanwhile I bought a 1/4" qev, Psy is lathing me a new Snapvalve and I'm thinking up my own version of the forced blowback bullpup.

Sounds promising

With my latest buy, being two diving bottles, I don't really care about lost pilot volume.

Finally! More sleepless night for the wife and kids though

[JDP12]

So JSR what would you say is more practical? A big thing I want is compactness, part of how I came up with it

[Brian the brain]

A big thing I want is compactness

That should be in my sig!

Ehm...
Psy could machine me some more snapvalves..
He could perhaps make a larger one...

On it's own its a very powerfull semi valve...just remember to let go of the trigger after the boom to prevent the hiss...

[JDP12]

Is that directed at me to prevent the hiss??

Yea I have more plans drawn up as well.

I think it'll work, I see no reason why it shouldn't

[jackssmirkingrevenge]

I would see it working as a semi auto looking something like this, but not as an automatic unless you find a way for the trigger to be pressed automatically, because it lacks the "stepped piston" element which makes pop-off autos work.

[psycix]

Such a mechanical pilot design will not work unless you seal using an o-ring and seal in the porting.
The mechanical pilot design features no force to press the piston against the porting, which is needed for it to seal.

[JDP12]

But there is force, a pressurized air bumper behind it. Which will be pressurized.

And I thought I would have to do the o ring seal of some sort- thanks

[jackssmirkingrevenge]

The mechanical pilot design features no force to press the piston against the porting, which is needed for it to seal.

In my 10mm piston launcher linked to earlier the rubber of the piston was compressed against the seat and held under compression by the trigger, but it was only good to 80 psi or so, obviously your modification works much better - though you need a lathe to be sure of having a perfectly centred piston.

[ramses]

Don't forget that air in the chamber must not be allowed to enter the pilot. Or the pilot must not be air-tight.

The later will waste air, and preventing it means just one more o-ring.

[psycix]

though you need a lathe to be sure of having a perfectly centred piston.

I can machine stuff and ship it over all of europe, including epoxy-rattlesnakecaves.
So far I've supplied BTB, sniper_hero and POLAND_SPUD with custom machined parts. Shipping will be somewhere between 6 and 20 euro's depending on weight and shipment type.

So if you are interested, you could take some work out of the epoxy department and have it arrive in machined aluminum, steel, or Delrin.

I'd be happy to machine parts for a low price for anyone, as long as he's a spudder.

[POLAND_SPUD]

@jsr psycix... damn it guys... I am designing something similar myslef...

what do you think about a design like this ?? the valve body could be machined in aluminium block while the 'spool' could be made from a threaded rod and machined disks with o-ring groves

I am trying to design something that could be used with HPA but piloted with regged down air