Blowback system, will this work?

[Zeus]

Sun Project, oh god, I want, but it's expensive as.

I don't have that GBB anymore sadly, twas a sweet gat, 4" barrel, Magpul'ed up, but it's in a better place now. I'll hook you up with some links, and if you ever want airsoft help bro, let me know.

Glad you got a WE, they don't kick as hard, but I reckon they're generally better for someone inexperienced with GBBRs. I wouldn't have picked anything but an AR/M4, but it's much the same system, and you'll love it heaps.

What colour and barrel length?

[wyz2285]

Well I'd have chosen a m4, but the scar uses the same mag as m serie and I got it by trading a medium grade aeg, couldn't say no to it.
I got the tan version, cqb barrel. I'm seriously into moding airsoft now, we'll have a lot to talk about

[bookyle]

wait, I have been searching everywhere trying to figure out how airsoft gbbs work. Send me some diagrams as well Zeus

by the way Gun Freal

so a hammer valve would be my choice

I thought hammer valve were not that consistent. I always thought that a 3 way with a chamber is more consistent. Or a solenoid 2/2 with a timer circuit

[Gun Freak]

A hammer valve with a well-made hammer is very consistent because it is self-regulating.

[bookyle]

Huh? Not sure what you mean by that. Are you saying that the hammer valve will account for lower pressure as you slowly run out of air?

But if we are talking about a regulated supply like a hpa tank wouldn't other valve be better?

[Gun Freak]

Yes that is what I'm saying.

With a regulated air source a QEV/3-way combo would probably also be consistent but I guess it would depend on the efficiency of the QEV and whether the 3-way is electronic or manual.

[bookyle]

What difference does electric or manual make?

Also, wouldn't 3 way+chamber be the same as 3 way+qev?

[Gun Freak]

Manual valve makes a difference because it may take you more or less time to actuate it each time which can have an effect on pilot speed and valve opening time. Electric valves always open at the same speed.

A 3-way on its own, without a QEV, would suffer from inconsistency due to this more than a 3-way/QEV combo would because in the combo, the 3-way is only a secondary valve.

[bookyle]

Ok, so an electric 3 way by itself should be about the same as a electric 3 way+QEV?

[Gun Freak]

With regards to consistency, I would think so. Let me say I've never tried one, but in theory they should open at the same speed every time, assuming a consistent supply of electricity (i.e. a battery that doesn't lose a significant amount of charge after each cycle). But a solenoid valve on its own probably won't be as strong as a QEV of the equivalent size. However, when dealing with small calibers, that won't always matter because your application may not require a huge blast of air. Many people have used solenoid valves for airsoft successfully.

[Brian the brain]

I say connect a " blowback-feel" piston to the barrel.
Just a Tee-off to a piston with a light counterspring.
Short stroke so it needs little volume and no bumper for maximum effect.

That makes it function independantly to the BFB, less hassle.

[bookyle]

so like a gas system on a real firearm? That might work. But I'm not sure about the consistency of such a system

[Zeus]

I can see that working quite well, you'd have to se GGDT to work out the rough pressure in the barrel at certain lengths to work out whereabouts is ideal, but yeah, could work well. Having the weighted "bolt" pushed forwards would enhance felt recoil too.

[wyz2285]

Well after reminding myself the existence of epoxy I machined the parts for a hammer valve.
It's a simple valve, yet steady to take anything up to unregulated co2. Obviously I'm keep going to try to make it work with regulated air, 10 bar.
I did a GGDT, using the dead space as the space needed for the air to recock the hammer, with a .20g bb I got a maximum barrel pressure of 0.9 bar, should be enough to push the hammer back to position.
Anybody see any flaws in the numbers I used?

[Gun Freak]

I see .02 grams for ammo weight instead of .20 which I think is a flaw 8)