SpudFiles

after admitting defeat from my old much to complex design (and after it met mr wall alot faster than anything shot) i decided to set myself one main grownd rule: i must obay by ocems razer (all things being equal the simplest option should allways be the best).
ive allso decided to take fmj's advice and look in more detail at the blow forward design, and wadda ya know he was right and it was just staring me in the face all the time, few alterations and here she is da da!!
in case your wondering i made the rear chamber larger so the piston would have a larger surface area making it easyer, and quicker, for the air to move it fowrard.

are you going to have a spring under the bbs or is the magazine going to be pointing upward??

i would go with a gravity magazine, spring ones are hard to get the right tension sometimes

i was thinking of making it air fed, this would allow the magazine to spiral around the barrel or hang (flexable pipe) giving a rambo style look.
i started work on the prototype but i kept the rear chamber the same size as the breach part, although i was unure how well it would blow forward i was pleasently suprised, the movement is very violent and when testing at 80psi it slipt from my hand (not expecting it) and shot me 6 times in the leg, it actualy broke the skin and now looks a mess this thing deserves respect and is no toy!!!
P.S spudshot its been said that you have an idea for a semiauto, id love to see it

hey guys i need help, im trying to perfect a prototype of this design BUT ive found a problem "how in the name of zuzes ass do you get an o-ring or seal inside the barrel in such a way that it wont blow out and doesnt stick out to far inside the barrel (block the bb completely)" its driving me crazy, please help

http://www.gizmology.net/pbm.htm is a great site with a homemade blowforward paintball mechanism. I wanted to build one but i cant find anything to use for the block.

THANK YOU!
All though this throws all our designs out the window . Why didnt I ever think of something like this? Thank you agian.

I wanted to build one but i cant find anything to use for the block.

What do you mean by block?

I think I will join the Christmas spirit, by giving out a link I found to be very helpful. Found <A HREF="http://airsoldier.com/~haveblue/tech/patents/">HERE</a>. It shows alot of popular paintball gun patents.

FreakyShotGlass: Thank You!!! You dont realize the amount of research I have done to find a design that works. Then you whip out one.

thanks for the link pimpman22 its got loads of info which im now studyin.
as for the other design iv seen it before but i wasnt impressed, its just a blow forward valve but not as good because it never closes itself? so in order to work it needs a logic circuit such as the 555 and a solenoid valve hense the project is now expensive. im looking for a system based puly on air.
plus i think he also mentioned on his site that it doesnt even work well?
just not convinced sorry

hey guys this project is nearing its end, i have modified and altered the design to make it simple to construct, built a simple mock up and am in the procces of testing now.
my working bbmg should be on the "finished bbmgs" part of this forum soon and whats more the mechenism is so small (plus the perfect shape) you could turn it into an uzi or mac 10 lookalike.

pimpmann, the block i refer to is the purple thing in the pic on that site.
glad i could help

iv been testing the prototype for an hour or so and im more than inpressesed with the power, rof and air consumbtion. i allso aded a cocking lever to the blow forward part (just for show) it recipricates realy quickly and looks incredable.
it still has a leak but once solved im going to build it properly