Idea for semi-auto layout

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Gun Freak
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Sun Jun 27, 2010 6:01 pm

I've been musing about semi autos and got an idea for a new design that I had never seen done before. Instead of making all the dead space between the QEV and the projectile, why not put the air cylinder and mag under the barrel with the cylinder facing up and the mag parallel to the barrel? the projectile could then be closer to the valve... here is a quick sketch...
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clemsonguy1125
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Sun Jun 27, 2010 6:03 pm

What would force the pin in the cylinder down to reload
That is all.
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Gun Freak
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Sun Jun 27, 2010 6:04 pm

It is a single acting, it has a spring. It was a rough sketch, sorry. Most commercial cylinders have the spring, so that's a given.
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clemsonguy1125
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Sun Jun 27, 2010 6:06 pm

Ok then what would force it up if a spring was forcing it down?
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Sun Jun 27, 2010 6:08 pm

Interesting idea, reminds me of a semi-auto shotgun. I would change the piston to be parallel to the barrel also with a system of linkages to load the projectile.
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Gun Freak
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Sun Jun 27, 2010 6:11 pm

clemsonguy1125 wrote:Ok then what would force it up if a spring was forcing it down?

The chamber is connected to the port of the cylinder like all other semi's.
Interesting idea, reminds me of a semi-auto shotgun. I would change the piston to be parallel to the barrel also with a system of linkages to load the projectile.
That would be very difficult and also unnecessary because well I can't share any of my design but I have a way to get around the bulkiness :)
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clemsonguy1125
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Sun Jun 27, 2010 6:13 pm

Gun Freak wrote:
clemsonguy1125 wrote:Ok then what would force it up if a spring was forcing it down?

The chamber is connected to the port of the cylinder like all other semi's.
Ok then it should work and all semi dont work like that
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Gun Freak
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Sun Jun 27, 2010 6:16 pm

Well most have the cylinder connected to the chamber to extend the piston stroke. I am just wondering why nobody has tried this way yet, it seems heaps better than the other way.
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Crna Legija
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Sun Jun 27, 2010 6:57 pm

i think its coz you cant do it with a store bought tee fitting also the air cylinder could crush soft ammo like paintballs.
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Sun Jun 27, 2010 7:43 pm

-_- wrote:i think its coz you cant do it with a store bought tee fitting also the air cylinder could crush soft ammo like paintballs.

You might also ruin the custom fitting you'll need to connect all of these elements. Imagine a steel ball being forced into an epoxy face. Even aluminum would dent after use. Then again, a dent may serve as a detent.

Whatever the case may be, I like it. The cylinder acts as a vertical fore grip, with easy positioning of a main piloting valve. This would be very ergonomic and attractive.
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deathbyDWV
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Sun Jun 27, 2010 8:46 pm

Hmm I might have to try this. With tees and a cylinder and .50 caliber and maybe uet the qev pilot to actuate the cylinder...?
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Sun Jun 27, 2010 9:11 pm

I like this layout.

The most likely reason layouts like this haven't been thought of is probably because many of the first guns to use a QEV and an air cylinder shot Nerf darts, and this layout isn't really possible for that.
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Gun Freak
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Sun Jun 27, 2010 10:08 pm

btrettel wrote:I like this layout.

The most likely reason layouts like this haven't been thought of is probably because many of the first guns to use a QEV and an air cylinder shot Nerf darts, and this layout isn't really possible for that.
Ahh, see I've never seen a QEV/cylinder/3way combo that shot nerf darts.
i think its coz you cant do it with a store bought tee fitting also the air cylinder could crush soft ammo like paintballs.
Well the whole idea was to make the cylinder stroke only long enough to get the projectile high enough so it has a straight path down the barrel, and no higher. I was planning on a homemade cylinder with custom stroke length and shaft length that would make for a more compact gun.


You might also ruin the custom fitting you'll need to connect all of these elements. Imagine a steel ball being forced into an epoxy face. Even aluminum would dent after use. Then again, a dent may serve as a detent.

Whatever the case may be, I like it. The cylinder acts as a vertical fore grip, with easy positioning of a main piloting valve. This would be very ergonomic and attractive.
I'm not exactly sure what you mean in that first paragraph. If the cylinder were to be commercially bought, then it would be rather long and could act as a foregrip. This design was to be put to a semi airsoft sniper in which case the cylinder would be homemade, like I mentioned earlier and would only be a few inches long, with the rest of the air chamber extending under and parallel to the barrel so it would be more sniper-like.
Hmm I might have to try this. With tees and a cylinder and .50 caliber and maybe uet the qev pilot to actuate the cylinder...?
The QEV actuating the cylinder would be a waste in my mind, since it doesn't need to actuate that fast to load the ammo.

Thanks for the positive feedback.
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Sun Jun 27, 2010 10:23 pm

Gun Freak wrote:Ahh, see I've never seen a QEV/cylinder/3way combo that shot nerf darts.
PVC arsenal made one quite recently for the competition.
Gun Freak wrote:
btrettel wrote:You might also ruin the custom fitting you'll need to connect all of these elements. Imagine a steel ball being forced into an epoxy face. Even aluminum would dent after use. Then again, a dent may serve as a detent.
I'm not exactly sure what you mean in that first paragraph
the upward force of the ammo being forced into the barrel will damage the barrel or the ammo if the cylinder pushes even a little too far, but this may not be a problem if you custom machine a cylinder.
Gun Freak wrote:cylinder would be homemade, like I mentioned earlier and would only be a few inches long, with the rest of the air chamber extending under and parallel to the barrel so it would be more sniper-like
why not just make the air cylinder the chamber?[/quote]
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Sun Jun 27, 2010 10:30 pm

Lockednloaded wrote:
Gun Freak wrote:Ahh, see I've never seen a QEV/cylinder/3way combo that shot nerf darts.
PVC arsenal made one quite recently for the competition.
Ah well I never really got into how that one worked... now I do.
LockednLoaded wrote: the upward force of the ammo being forced into the barrel will damage the barrel or the ammo if the cylinder pushes even a little too far, but this may not be a problem if you custom machine a cylinder.
That's what I thought he meant.... Yeah it would be easy to just grind down the cylinder until it no longer pushes the ammo too hard.
Lockednloaded wrote:cylinder would be homemade, like I mentioned earlier and would only be a few inches long, with the rest of the air chamber extending under and parallel to the barrel so it would be more sniper-like
why not just make the air cylinder the chamber?[/quote]
Not understanding that either... If you mean to integrate it into the chamber, it already will be. Got it all planned out, just haven't had the time to sketch the full design.[/quote]

Sorry this post is a little messed up but I don't feel like fixing it, you should get what I'm talking about.
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