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Select-fire, double valved, gas-operated (concept w/ .gif)

Posted: Sat Oct 24, 2009 11:59 am
by Tsukiten
Sup guys ;D
Here's a firing action I designed two days ago. It's heavily inspired by the way modern automatic rifles work. The neat thing about this design is that it cycles AFTER the bb has been fired, and always fires even pressures are too low to cycle it (you cycle it manually, in that case) .
(Animation takes a while to load)
Image
(Note: I have not drawn all the rubber bands and springs it would be using.)

It works with two hammer valves. In a conventional rifle the gas from the cartridge drives both the piston and the projectile. In a gas gun pressures would have to be too high to still be safe, so I came up with using two valves instead. Once the hammer strikes the first valve it releases a second hammer, which strikes the second valve. The first valve drives the bb, the second the bolt.

But, the best part of it all...

...I found an easy way to make a fire-mode selector switch for it! :D
Image

The fire-selector is something that I still need to improve a bit, though.
Anyway, I'm quite excited about it, and I think I'm going to give it a go some day.

Any thoughts? Better solutions? Criticism?
Please do reply! :o

Posted: Sat Oct 24, 2009 12:06 pm
by jackssmirkingrevenge
Looks like it would work, if you have the right resources to fabricate the parts with necessary precision, but it's too complex in my opinion. How about using gas bled off from the barrel to cycle the action, as in gas fed rifles?

I've talked down the idea in the past for use in pneumatics but after seeing the way my FX Monsoon works I think it would be viable with the right parameters.

Posted: Sat Oct 24, 2009 12:12 pm
by Tsukiten
jackssmirkingrevenge wrote:Looks like it would work, if you have the right resources to fabricate the parts with necessary precision, but it's too complex in my opinion. How about using gas bled off from the barrel to cycle the action, as in gas fed rifles?
Using gas from the barrel to cycle would require alot of pressure, I assumed. This way one may use lower pressures, safer and easier to archieve.
And yes, I find it also a bit complicated for my taste, but I hope to simplify the design with some ideas coming from the members here. :wink:

Posted: Sat Oct 24, 2009 12:29 pm
by jackssmirkingrevenge
Have a look here.

What the Monsoon does is essentially have a suppressor where the rear wall isn't fixed but is actually a piston coaxial with the barrel. After the pellet passes, air fills the suppressor chamber and pressurises it, pushing the chamber back and recocking the mechanism.

Granted, this needs at least 1,500 psi to work on the Monsoon, but the cocking effort required is more substantial than your design would need. Also, amateur spudguns tend to use lower pressures but larger volumes of air, so in order to increase the force a piston with a larger surface area should compensate for the lack of psi.

Posted: Sat Oct 24, 2009 1:00 pm
by Tsukiten
jackssmirkingrevenge wrote:Have a look here.

What the Monsoon does is essentially have a suppressor where the rear wall isn't fixed but is actually a piston coaxial with the barrel. After the pellet passes, air fills the suppressor chamber and pressurises it, pushing the chamber back and recocking the mechanism.

Granted, this needs at least 1,500 psi to work on the Monsoon, but the cocking effort required is more substantial than your design would need. Also, amateur spudguns tend to use lower pressures but larger volumes of air, so in order to increase the force a piston with a larger surface area should compensate for the lack of psi.
Haha, Moonsoon's operation sounds pretty cool to me.
But I'm already seeing ways to reaaaly simplify my design (I'm a bit stubborn :) ), so stay tuned!

Posted: Sat Oct 24, 2009 1:39 pm
by boyntonstu
VERY creative!

Bravo!

BoyntonStu

Posted: Sat Oct 24, 2009 1:58 pm
by psycix
Looks good, but complex.
I noticed that it may (not will, may) have a resetting problem right here:
A small intended leak could solve it.