Magazine fed 40mm finished

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
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Ragnarok
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Sun Feb 28, 2010 6:22 am

Solar wrote:haha, yeah, regarding that previous post... I sat up and stared at it for hours last night after it was complete. It's been a long time in the works. Nice to see it in reality for once.
I've had that with a few things. A sense of wonder that whatever it is now exists in reality coupled with "Am I really capable of making this?" - very weird.
Does that thing kinda look like a big cat to you?
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psycix
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Sun Feb 28, 2010 9:04 am

Hubb wrote:There is no need for a comment other than WOW.
Yes there is:
"Video, please"


Looking good there Solar!
Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

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Brian the brain
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Sun Feb 28, 2010 1:26 pm

I've had that with a few things. A sense of wonder that whatever it is now exists in reality coupled with "Am I really capable of making this?" - very weird.
Been there.. :D

Still never satisfied.
I parrot the need for a video.
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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Solar
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Mon Mar 01, 2010 3:06 am

No video yet, but here are some more detail pics.
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The small black hose is being replaced by a braided line and eventually will be internal to the grip frame. The detail of the bolt shows the air holes and the layers of tubing that make up the bolt/valve combo. The center air hole in the bolt is also visible. You can also see the porting used for the air to flow through the receiver which is plugged on the base of the gun. I enjoy how it can be sat on its side or upside down and won't roll away like the revolver. I promise a video soon. I will chrono and decibel meter.

You can see the polished area worn on the bolt across it's travel. The bolt will be hard anodized and eventually self lubricating with impregnated metals.
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Brian the brain
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Mon Mar 01, 2010 3:13 am

Great work.
Does the muzzle porting improve accuracy?






(edited spelling.. and to answer your question below psy, yes I have... :D )
Last edited by Brian the brain on Mon Mar 01, 2010 8:47 am, edited 1 time in total.
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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psycix
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Mon Mar 01, 2010 7:34 am

Have you ever considered to make a bullpup?
Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

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iknowmy3tables
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Mon Mar 01, 2010 10:34 am

yeah you could probably make a bullpup, have you considered using a sliding barrel design? or possibly a porting in front of the magazine like in trettel's FANG
if you do it correctly, you can have less dead space then what your current design has.
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Solar
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Mon Mar 01, 2010 3:13 pm

Yes I have thought about a bullpup version. The back of the firing piston would be about where the new stock would go and the trigger assembly in front by the tanks. In this version of magazine, even the mag itself could be fashioned into a grip, but I will be going to a wider mag, so that would not be feasible. I am also concerned how close the front of the mag would be to the rear of the grip for ergonomics, but I will continue to keep the bullpup design in mind.

The FANG configuration at first glance would not work properly with this design since it uses a piston that keeps the receiver in a closed bolt position when charged. This launcher uses the air from the shot behind a piston/bolt/valve that needs to feed from behind.

I have not yet tested the ballistics of the barrel porting. I am waiting for the new rounds this week that we are having made to specification so we can get accurate readings. I will be able to compare at that point. In the earlier versions with the muzzle brake, we had issues with noticeable tumbling of the finned rounds. We could see the tails get kicked around from the turbulence.
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Solar
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Mon Mar 01, 2010 3:20 pm

Not sure if I mentioned this before, but the gun won't open the bolt/valve unless there is about 130 psi behind it. If the gun is at 300psi and you take a shot, the gauge never drops below that. It seems to get sealed up before it wastes the whole ballast of air. Interesting that at a 1:1 ratio, it is getting sealed at about the same time the barrel and ballast are equalized when the projectile is at the end of the barrel. This is how I am thinking anyways...
iknowmy3tables
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Tue Mar 02, 2010 9:03 pm

wow then I'm not sure how this gun work? could you explain the design of the bolt/valve, a crude diagram would be helpful
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twizi
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Tue Mar 02, 2010 9:09 pm

OMG
i cant believe i noticed this
another great weapon solar

wow
dont play with airsofter with 1000$ gun and play with a 5 dollar pair of glasses
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Solar
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Wed Mar 03, 2010 4:02 am

http://www.deadlywind.com/tech/marker_animations/

If you go to this page and look at the automag or freestyle you can see the principle at work. Basically the bolt is a tube that has a suspended rod with an o-ring in it that slides into the air feeder tube that the bolt slides over as well. Once the bolt is fired deep enough into the receiver, the inner rod/plug opens up and lets air into the receiver through holes in the bolt. After the shot it returns by spring force.
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Wed Mar 03, 2010 7:58 pm

oh I see, I would have never guessed it just from the picture,

so is it like this like this?
Image

or did you use a higher pressure pilot and the diagram below
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Solar
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Wed Mar 03, 2010 8:29 pm

The main air valve is a piston that is separate from the bolt valve combo. When the air rushes from the main ballast to the air feed tube it is the full blast that will launch the projectile. It is plugged on the inside diameter of the tube, while the outside diameter is where the bolt rides with springs encapsulated between.
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Wed Mar 03, 2010 8:49 pm

oh so it's a just a piston valve and a blow forward bolt
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