My First QEV rifle

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nz_cannons
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Fri Oct 12, 2007 11:40 pm

Its been a while since I last posted a cannon so here we go.
I managed to get hold of a Quick Exhaust Valve finally, seems their not very common in New Zealand.

I gave up trying to find some place to order one from so I went into town. Ebay was asking like 30 bucks for shipping, on top of a huge price, "are you having a laugh?"

I was directed to a place that specialized in hydraulic and pneumatic services and enquired about one.
There were boxes of the things, and I was like "sweet."

The dude there gave me a good deal of $20 for a "3/8"inch one. I will go back and get a 3/4 inch or 1/2 inch one at a later date, probably for around 30-45$.
This particular one is all steel and thats about all I know, it has no markings except for an arrow, don't know about the pressure rating but I took it up to 150psi and it seemed ok.

Now on to the gun. I didn't want to wait to next week to get fittings so I searched around for stuff that I could use at home. I had an old sodastream co2 canister so I used that as the main chamber, might be a bit small, buts its enough for now.

Luckily the thread was the right type and size so it connected nicely to the QEV. The opening in the cylinder isn't that big so I might drill it out at some stage to increase air flow.

I cobbled together some "Hanson" fittings that were lying around and the bits of my last cannon to make the charging and exhausting system. I know its too big for this size gun but its all I had. I managed to crack the ball valve case while screwing it on, piece of plastic crap. But I just used the other end that was ok and it works fine lol.

I didn't have any fittings for the barrel. I wrapped electrical tape around the end of the aluminum pipe that was to be the barrel until it was the right size to be screwed into the QEV. It actually screwed in quite tight and straight. I secured it with hot glue. I haven't had any problems with it so far, it doesn't leak at all, but Im just waiting till the projectile jams and the whole barrel blows off lol, but it should be right.

Like I said I've had it up to 150psi with no problems, the valve works good as and it keeps its pressure. I've been shooting bits of wooden dowel out of it and it seems to have a bit of power. Need to find something better then that though, something that will fly straight and have a bit of weight.

Specs.
-Barrel length is 1meter and diameter is 10mm (internal).
-Chamber volume I estimate to be around 400ml.
Attachments
qev4.jpg
qev3.jpg
Close up of the barrel/QEV connection.
Close up of the barrel/QEV connection.
qev1.jpg
The sharpened rod after I pulled the dowel off. Its buried in there about 25mm and I couldn't pull it out, I tried.
The sharpened rod after I pulled the dowel off. Its buried in there about 25mm and I couldn't pull it out, I tried.
This is just a bit of dowel with a sharpened rod stuck into it and a squewer for a tail. I needed something that would fly straight because everything else I was firing would just hit the target sideways.
This is just a bit of dowel with a sharpened rod stuck into it and a squewer for a tail. I needed something that would fly straight because everything else I was firing would just hit the target sideways.
Last edited by nz_cannons on Sat Oct 13, 2007 4:25 pm, edited 1 time in total.
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MrCrowley
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Sat Oct 13, 2007 12:39 am

Finally another Kiwi that makes decent cannons. I had to go all the way to America to get my QEV :P

http://www.spudfiles.com/forums/viewtop ... tml#123928

Where abouts in NZ are you? Im up in Auckland.
Whats the shop called?
nz_cannons
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Sat Oct 13, 2007 2:19 am

Cheers, yeah Im in Nelson huh.

Its not really a "shop" as such, its an engineering outfit that specializes in hydraulic and pneumatic equipment. These valves are used to speed up pneumatic rams (something like that) so thats why they had them in stock. There should be plenty of places in auckland that deal with these types of things, don't bother with Enzed because they only deal with hydraulic stuff. Just search the yellow pages for pneumatic services or something.


Just one note, this gun was more of a prototype then anything. My next one will have breech loading, bigger valves, bigger tanks, slim design, hopefully something that has accuracy and resembles a real rifle.

Right now im just trying to think of something to shoot out of the thing.
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MrCrowley
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Sat Oct 13, 2007 2:48 am

Ah right, thanks. It just good seeing another Kiwi into this hobby. I've been causing havok here in NZ by myself for too long :wink:

Do you know how the PVC system works in NZ? It's quite different from the American one, so if you need to know anything about plumbing in NZ just hit me up I know it all. :P

Just checking, do you know how to identify pressure rated PVC pipe in NZ? Better safe then sorry.
nz_cannons
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Sat Oct 13, 2007 3:05 am

Yea man, Im pretty on to it aye.
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Redcoat
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Sat Oct 13, 2007 3:16 am

nz_cannons wrote:"are you having a laugh?"
Seen Extras? :wink:

Anyway, Nice gun. When you pull the ball valve trigger does the gun jerk up and around a bit?


Damage pics or video would be sweet.

Happy Spuddin'
Poo.
nz_cannons
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Sat Oct 13, 2007 2:45 pm

Lo, yea good show.
Um, nah it doesn't move around too much huh. The ball valve is not very stiff to move and that heavy cylinder helps to keep it stable.
Will try get some damage shots up later today.
nivekatoz
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Sun Oct 21, 2007 2:40 pm

You should design it a littel different.... For example make the cylinder horizontal..put the cylinder under the barrel...and come up with a kick ass stock........
nz_cannons
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Sun Oct 21, 2007 5:01 pm

Yea man, ive made a new version of it thats like that, it's way more powerful. I'll have it up here soon. Much cleaner design.
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battlemonkey
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Sun Oct 21, 2007 6:27 pm

Do you live in hamilton or is it only me terrorising H town
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MrCrowley
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Sun Oct 21, 2007 7:16 pm

He lives in Nelson I think it was, I got relatives in Hamilton, don't terrorise it too much :P

shud_be_rite lives up in Auckland with me i'm sure, there is also someone else up in Auck but they don't come on anymore.
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battlemonkey
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Sun Oct 21, 2007 7:26 pm

only time people got terrorised is when i loaded a water ballon into cannon and sprinkler valve battery shortcircited..... that went a longgg way down street
nz_cannons
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Mon Oct 22, 2007 4:33 am

Lo, yeah nelson man.
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Mon Oct 22, 2007 4:40 am

That is some really good tough work you are doing there bro.
How do you just manage to find all the parts? I love that shit you got!!
Yeah, keep up the good work :D
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ninjafroglet
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Wed Nov 21, 2007 2:07 am

I'm from auckland too =o, i'm halfway throguh making a combustion, i just need the time to do it...

Cool cannon :D
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