well... if you got enough oxygen/air,a good barrel and airtight fit. I've tried it many times. At first i didn't believe it too... I'm actually suprized it did go through.

On the other end theres a rubber o-ring with a hole big enough to fit a 6mm bb airtight. I usually spray 1.5 sec in that hole first... wait about 40 seconds. Then i pump 4 times with a bicycle pump. No, it's not pressurized. After pumping fresh air i quickly close it with a bb.

fire, BWAM! Through ...

Nice and clean! 8)

btw this concept means that in idle mode the bolt is in open posistion and only closed when trigger is fully pressed and ignites with a piezo.

After releasing the trigger... the triggerspring will be powerfull enough to pull out the empty case. Maybe the the spring of the piezo ignitor will provide ...

Well I'm planning to use the trigger as a source to move the bolt back by using gears, just fingerpower. Mainly because the bolt just only moves back and forth by 1 inch.

After the bolt moves back, the empty case will be pushed out by another case below uhm like this (got my picture order messed ...

Here are some pics. Next step is to build the magazine holding area which holds the assembly together shown in the 1st pic.

hiya! ...indeed the concept is identical!

Cool project you got there! 8)

Hi! (I could be a little bit Engrish :D )

I've recently made my first "spud gun"... well actually it's a small piece of PVC (2cm diameter x 6cm length). Both ends superglued with rubber O-rings (the ones you use for watertaps). On one end I've slightly plugged in a main wire (with 2 or more colored ...