My first air cannon. Going to be used to shoot nerf balls :]

[Lockednloaded]

A QEV is a right angle valve, so an inline setup is not really what it's made for.

I'd reccomend a design like this

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[Jarrado]

Is this the proper way to run it? If it is, I'll need to do something else. It REALLY needs to be inline. Unless I could hide some 90's in the grip or something.

[MrCrowley]

You need something like this:


Or if you're keeping to 125PSI and under, just go with a 1" sprinkler valve. Or have I missed something and you have already discussed this option?

edit: in reference to your picture 'air out' is the chamber, 'air source' is the pilot and 'pilot' is where the barrel goes.

As for my picture above, you would remove the solenoid and modify the top so you can attach a pneumatic pilot valve. I see you said sprinkler valves are bulky; while they're larger than 3/4" QEVs they're about as small as you can get for in-line valves like that.

[Jarrado]

Gotcha. Yea. Mixed that up real good. haha

I'll see about using what you suggested there. Its basically a diaphragm valve right?

I originally got the QEV to do inline, I was mistaken. I got that QEV4 for like $20 or something, so not a huge loss. LOL

This stuff is pretty new to me, but machining isnt. I'll be getting some tap sets, so I dont need so many fittings. Already have some large taps for NPT, so I may be able to do an over under, that looks decent, then wrap it up.

Or... I could use flexhose?

[Jarrado]

Ended up going with 2 LAW inline co2 12grams with a shutoff at the co2 (2000psi carbon steel ball valves) and a 3/4 ball valve to actuate. More simple. Lighter.

Im going to drill and tap the expansion chamber for a 1/4"NPT gauge. I want to have the chamber not go over 100psi even if all the co2 is dumped accidentlly. I want to get 2 shots at 60 psi or so off one co2 12 gram. Thinking a 6'' expansion (plus 1-2 with fittings) and a 1 foot barrel. Overall would be about 2-1/2 feet.

Going to take the QEV design that "locknloaded" used and flip it into a mortar.

SCH40 2" design and run the psi up to about 100psi to launch canister rounds 400feet.

Blow off safety @125psi, gauge (hooked into a T) to see PSI and a cap for safety.

Power source will be a remote rig to be worn by the mortar carrier.

Now. Since I have a few extra 2000psi ball valves, should I add one at the co2 entry to further add safety? Or would that just add to much? I want it to be decently easy to use.

I'm planning a 3-1/2 foot 2" barrel and a half that volume expansion.

[Jarrado]

Irritating. Well. It shot ok, but leaky all over. These china fittings are garbage.

I think....... I may ditch the 12g all together (getting too expensive). I think I will make one nearly exactly like the one that lockednloaded, but I'm using Co2 with my QE4 valve........ um.....

I have like 10 co2 bottles, is there a way to mod one to be an air chamber? I take it I would need some kind of adapter?

Or I can find a used fire extinguisher instead? Any ideas on where to find these<<<

[Jarrado]

Well. After alot of reading and some help from a few guys here and airsoft and pb sites...... I think I finally understand what I need to do.

I'll be back with the culmination of what I've learned in a bit in the form of a launcher.

Thanks for putting up with the dumb questions haha

[Jarrado]

OK. Well. With the help of a few people I think I understand the air, barrel, projectile, chamber, valve relations.

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I'm going to use a QE5 elbowed into a sch40 2''X40" with a large 150CI chamber. I'll start @ 80psi. This will be my mortar for shooting at a 45* in a fixed position.

I will pilot it with a air blower, then a 3 way DCV direct spool valve and lastly a small 1/4 QEV. I may combine them all together if I have time.

I'll be using an electrical expansion sch80 coupling as a seal for my slide open action. I'll have an orings on both sides.

==========

I'll be testing these power sources:

Palmers regulated co2 remote setup with a 2000psi ball valve as a cutoff.

1 and 2 stage bike pump. connected to a car tire valve (<will have on as a backup in case i run outta co2)

12g's. I'll be triple checking the cylinder volume and have a psi gauge and blow valve installed in case.

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As soon as the loctite dries, I'll test it and get pictures up.

[dewey-1]

Here is an example using Humphrey QE5.

[Jarrado]

That is nearly exactly what I had in mind now.

I'll be using a fire extinguisher, so I may end up dropping it into a homemade rifle stock.

I will most likely end up filling from the chamber side and modding the QEV to close faster. Unless there is a better way to do it? I need to maintain auto filling for quick reloads.

[jackssmirkingrevenge]

I will most likely end up filling from the chamber side and modding the QEV to close faster. Unless there is a better way to do it? I need to maintain auto filling for quick reloads.

If you are using a three-way valve as a pilot, it shouldn't take more than a couple of seconds to re-pressurize your firing chamber.

[Jarrado]

Basically have my main cannon done. Have a 110ci chamber, QEV5 (3/4), and an air blower as the pilot. Running at about 90psi.

If I fill from the pilot side via a high pressure on/off valve on a 3 way T, I could get more shots per fill correct?

I'm running a 20" breech loading barrel. So far, I've been able to hit 250ft no problem. But I can tell there is alot of wasted co2. I may need to seal the breach better.

Thanks for the advice, its been extremely helpful. I'll post up pics when its been completed, painted and field tested.