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Mini BBMG Idea

Posted: Thu Feb 11, 2010 6:13 pm
by clemsonguy1125
Well heres a BBMG idea I came up with the other day. Im pretty sure it would work a a semi auto gun. It works by air pressure coming through a schrader valve and building up pressure until it pushes a spring loaded epoxy piston forward past a hole to the barrel. The only problem is what kind of mag to attach and Im not sure if it will cycle automatic. Also Im not sure about the piston seal.

Posted: Thu Feb 11, 2010 10:11 pm
by POLAND_SPUD
it's exactly the same as one of JSR's prototype that didn't work

the problem is that the piston would be pushed past the hole and would stay there slowly letting air to leak out

Posted: Thu Feb 11, 2010 10:25 pm
by clemsonguy1125
Oh it is,I hadn't seen that but if I used a stronger spring and lower pressures would the pressure build pust it back and the strong spring return it back

Posted: Fri Feb 12, 2010 12:12 am
by jackssmirkingrevenge
clemsonguy1125 wrote:If I used a stronger spring and lower pressures would the pressure build pust it back and the strong spring return it back
No, as POLAND_SPUD pointed out essentially what you'd make is a farting machine, or an angry wasp that cycles too fast to be useful.

If you want it to have any chance of working you have to introduce a pop-off element that will allow pressure buildup then piston movement - my work in this area is well documented - essentially it should look something like this:

Posted: Fri Feb 12, 2010 3:55 pm
by clemsonguy1125
jackssmirkingrevenge wrote:
clemsonguy1125 wrote:If I used a stronger spring and lower pressures would the pressure build pust it back and the strong spring return it back
No, as POLAND_SPUD pointed out essentially what you'd make is a farting machine, or an angry wasp that cycles too fast to be useful.

If you want it to have any chance of working you have to introduce a pop-off element that will allow pressure buildup then piston movement - my work in this area is well documented - essentially it should look something like this:
Ok Ill give this a shot but might end up using it in a semi auto pellet gun

Posted: Fri Feb 12, 2010 4:31 pm
by Skywalker
[quote='jack']my work in this area is well documented[/quote]

Wow, sounds like something you'd expect to hear in a research paper, not a spudgun forum! :lol: But it's true, Jack basically does all the research around here, with his crazy epoxy rapid prototyping method, while we sit around and wait till he comes up with something so we can copy it!

Posted: Fri Feb 12, 2010 4:39 pm
by clemsonguy1125
Ive looked through his stuff and been amazed but id never actually seen his idea similar to this

Posted: Sun Feb 14, 2010 1:58 pm
by jackssmirkingrevenge
Skywalker wrote:Wow, sounds like something you'd expect to hear in a research paper, not a spudgun forum!
Well, I do come from an academic background and there's nothing wrong with taking R&D seriously, even if it is just for blowing holes in stuff ;)