JHQJR-Revamped QEV Gun

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frocksie
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Wed Nov 21, 2007 10:01 pm

This gun started out as the QEV-75M, seen here:http://www.spudfiles.com/forums/qev-75m-t11245.html.

I then reconfigured it to its current state, due to an inability to leave anything alone and my love of tinkering.

SPECS
Valve: 3/4" QEV
Pilot: 3/8" ball valve
Barrel: 4ft of 1/2" copper
Chamber: 3 ft of 3/4" copper
Operating Pressure: 150psi

For the bolt action the barrel is inside 3/4" CPVC, an almost perfect fit.

The bolt isn't sealed with an o-ring, as the 1/2" copper is a tight fit in the 3/4" CPVC coupling.

All together this gun has cost about $110, but would have cost a lot less if I had formulated this design from the start.

GGDT predicts about 1000 fps with 150psi and 5oz nail dart.
Attachments
QEV with bolt-action and stain 004.jpg
This is the pressure gauge, pilot, and schrader valve
This is the pressure gauge, pilot, and schrader valve
bolt open
bolt open
bolt closed
bolt closed
QEV with bolt-action and stain 011.jpg
The four darts at the right are regular darts, and accurate up to 30ft, as that is the maximum distance I can test. <br />The Dart on the left contains three nails, and these nails impart spin on the projectile.
The four darts at the right are regular darts, and accurate up to 30ft, as that is the maximum distance I can test.
The Dart on the left contains three nails, and these nails impart spin on the projectile.
“He who controls the present, controls the past. He who controls the past, controls the future.”
-George Orwell
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Maniac
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Wed Nov 21, 2007 10:08 pm

sick canno man i love it great job post damage pics as soon as possible and a vid would be nice too. did you spray that cpvc black?
Coodude26 wrote:
People who laugh really hard at stuff that pisses you off/you getting hurt, who then say "I'm sorry, I can't stop" but you know they easily could.

Mr.C: That's not as easy as you think. It's like me kicking you in the balls and telling you to stop crying.
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Maniac
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Wed Nov 21, 2007 10:15 pm

love british qevs im assumig its a british one they seem to be streamlined like yours most of the time. edit oops sry for the double post
Coodude26 wrote:
People who laugh really hard at stuff that pisses you off/you getting hurt, who then say "I'm sorry, I can't stop" but you know they easily could.

Mr.C: That's not as easy as you think. It's like me kicking you in the balls and telling you to stop crying.
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Hubb
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Wed Nov 21, 2007 10:52 pm

Agreed. This is one fine creation.
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mega_swordman
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Thu Nov 22, 2007 4:16 am

Very nice. I tend not to like QEV cannons, but this one looks really good. Nice job. I also really like your trigger system.
"Never tell people how to do things. Tell them what to do and they will surprise you with their ingenuity." George S. Patton
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frocksie
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Thu Nov 22, 2007 6:54 am

@Maniac, yeah I used Rust-Oleum, and then I gave it a coat of Polyurethane. Actually, the QEV isn't British, I got it from Fastenal.

I stained the handle, stock, barrel supports, and bolt-action handle mahogany, and this dried quickly, but I then polyurethaned all of those items, but due to weather in the low 30s, it never dried, so I had to rub it all off with paint thinner.
Lesson: Don't polyurethane in temperatures below freezing.
“He who controls the present, controls the past. He who controls the past, controls the future.”
-George Orwell
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psycix
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Thu Nov 22, 2007 8:59 am

Awesome gun!
Now paint it some and its double awesome :D
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Zen///
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Thu Nov 22, 2007 9:07 am

Very nice, goes with up there copperhead prime and heal.
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Ragnarok
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Thu Nov 22, 2007 10:58 am

Zen/// wrote:Very nice, goes with up there copperhead prime and heal.
What's interesting is that the last version looks like Copperhead, this version looks more like HEAL... Not quite as large, nor does it have the same valve or pressure, but I can still see it being a very good hole puncher.

Very nice work... hope it's fun for you.

The GGDT sounds way off though. I can only just about hit 1000 fps using a projectile weighing a 1/5 of an ounce, a larger valve, twice that pressure, and double the bore area.
You'd also have to get a 2650% efficiency for that to work, so forgive me when I say you've made some sort of mistake.

Can you supply a screen shot of the GGDT?

EDIT(s): Slight calculation and spelling mistakes.
Last edited by Ragnarok on Thu Nov 22, 2007 2:35 pm, edited 3 times in total.
Does that thing kinda look like a big cat to you?
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MaxuS
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Thu Nov 22, 2007 1:50 pm

I could swear this was a topic about Frocksie's revamped QEV gun, and not HEAL...
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Ragnarok
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Thu Nov 22, 2007 2:31 pm

It is, but I at least made a valid contribution about frocksie's GGDT flawed results in my post. You don't seem to have advanced discussion much.
Does that thing kinda look like a big cat to you?
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MrCrowley
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Thu Nov 22, 2007 3:05 pm

MaxuS wrote:I could swear this was a topic about Frocksie's revamped QEV gun, and not HEAL...
Rag's post seemed legit enough to me.

Very very nice copper cannon, it looks great. The stock looks awesome as well. You did a good job on this one, Keep it up.
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Ragnarok
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Thu Nov 22, 2007 3:34 pm

I don't see quite what the problem was either. I don't see quite how a brief comparison of appearances (based on a post that Zen made, I didn't originally bring it up) causes a problem.
I assume it's pretty obvious I'm what I'm referring to when I'm talking about getting those velocities, but I wrote the note then decided an example helped to explain the unlikelihood of the result being correct.

Anyway, I just looked at the soldering, very neat, much better than the messes I made when I first tried soldering - in fact, it's better than my current soldering is half the time. (I assume you haven't done much soldering since your last version of this, which you said was your first time soldering.)
Does that thing kinda look like a big cat to you?
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MaxuS
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Thu Nov 22, 2007 4:31 pm

In almost every thread, you mention HEAL, yeah its a good gun but sometimes it does sound like you cant keep it out of the conversation, like its always a competition of whos got the best.
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Ragnarok
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Thu Nov 22, 2007 6:00 pm

Maxus, I would never be so insulting as to say HEAL was the best, and I don't bring HEAL up for such crude reasons. It's good, but there are so many cannons I hold in very high regard.
When I talk about HEAL, it's because someone else has, or I'm actually documenting the trail of my thoughts, and I am honestly thinking about something to do with it. It's not like I am the only person that ever mentions their own cannons by name in other topics.

Now, let's stop filling up frocksie's topic with responses to a comment that I probably should have ignored in the first place.
Does that thing kinda look like a big cat to you?
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