full or semi automatic airgun

Building or modifying BB, Airsoft, and Pellet type of guns. Show off your custom designs, find tips and other discussion. Target practice only!
poppamies
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Sun Jun 07, 2009 2:06 pm

im making dragunov svd airgun wich works by a 20oz paintball co2 tank. i need full and/or mechanism to it. it takes 6mm metal bbs out of the magazine and feets them into the barrel. how i can make the machanism so thet the slide slides when it shoots bbs. its then very realistic but it 1:2 of the size. please help me!!!!!

edit: it could be uced with air or electrick. i like electrick because the power source doesnt cost anything. if somebody can tell me how to do it. im new on spudfiles and i have few spud guns and pneumatic guns but i want to do a accurate airsoft sniper rifle. help me!!!

sory. full or/and automatic mechanism. sorry bad english. im from finland and i lern english at school but im not very goos at it
Last edited by poppamies on Sun Jun 07, 2009 4:00 pm, edited 1 time in total.
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psycix
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Sun Jun 07, 2009 5:06 pm

i lern english at school but im not very goos at it
:lol: True words. Maybe even an understatement.
Use spellcheck!

And don't double-post like that.


For fully-automatic fire, you could build a cloud/vortex bbmg, or you could do some research on QEV+popoff.
Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

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dudeman508
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Sun Jun 07, 2009 5:59 pm

psycix wrote:
i lern english at school but im not very goos at it
:lol: True words. Maybe even an understatement.
Use spellcheck!

And don't double-post like that.


For fully-automatic fire, you could build a cloud/vortex bbmg, or you could do some research on QEV+popoff.


He was looking for a bolt that slides forward when he fires. This would be a blow forward bolt, you can PM me or JSR if you want to know how it works. Like Psicix said vortexes and clouds are very affective for full auto with bbs.
Dave_424
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Sun Jun 07, 2009 6:15 pm

I have a feeling that he wants blow back, for realism in his SVD style airsoft rifle.

I would suggest a QEV with a single acting cylinder in the chamber. When the chamber dumps it's air out of the barrel (Firing) the cylinder will pull/push the bolt and feeding mechanish backwards to load a new bb into the chamber and when pressure rises back into the chamber, the bolt moved forwards into its firing position.

Dave
poppamies
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Mon Jun 08, 2009 5:05 am

i think im going to use a homemade qev with 8mm barrel and 15bar pressure.it doesnt make the slide so real but who cares? i make that the back of the slide is botl action and the magazine is just fake for looks. or maybe i make at bbmg or cloud. the svd body is very hard to make so i spend all the summer for making this.
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dudeman508
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Mon Jun 08, 2009 9:09 pm

poppamies wrote:i think im going to use a homemade qev with 8mm barrel and 15bar pressure.it doesnt make the slide so real but who cares? i make that the back of the slide is botl action and the magazine is just fake for looks. or maybe i make at bbmg or cloud. the svd body is very hard to make so i spend all the summer for making this.
A homemade qev is called a barel sealing piston valve, but they esentialy do the same thing.
Last edited by dudeman508 on Wed Jun 10, 2009 10:36 am, edited 1 time in total.
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Technician1002
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Mon Jun 08, 2009 9:33 pm

dudeman508 wrote:
poppamies wrote:i think im going to use a homemade qev with 8mm barrel and 15bar pressure.it doesnt make the slide so real but who cares? i make that the back of the slide is botl action and the magazine is just fake for looks. or maybe i make at bbmg or cloud. the svd body is very hard to make so i spend all the summer for making this.
A homemade qev is called a piston valve, but they essentially do the same thing.
Not all piston valves have the right configuration or dimensions to auto snap open and rely on the speed of the pilot. Chamber sealers and large seat to OD ratio pistons are not Quick Exhaust Valves. To qualify, they must snap open inspite of a slow pilot, large pilot volume due to a long trigger hose, etc.

It is true most barrel sealer piston valves here do qualify as a QEV.
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