SpudFiles

I see your point, my solution to that potential problem with my design would be to add rubber washers in the gap.

and epoxy them.

what would be the burst disk? aluminum foil?

Probably plastic tape as I used in my 6mm burst disk.

Jack,

I've just realised, why do you want this bit machined, surely your 6mm cartridge above is just the ticket? Or am I missing something?

Other thought, have you tried casting threads in epoxy? My local DIY store has some "patte à malaxer" (a two part thick epoxy paste), you work together like dough which you can squeeze into a nut, wait for it to set and then undo out of the nut. Likewise you can form it round a bolt and undo the bolt... you can then happily thread your epoxy "bolt" into your "nut" and the whole thing is epoxy.

Just a thought.

The one above was made with brass compression fittings I found lying around, they wouldn't make for a very clean cartridge.

I've cast threads in epoxy before to fit a suppressor on my Yunker:





The cartridge in question though requires a bit more "beef", I'm worried the epoxy threads would wear out from repeated use.

I’m surprised that you jack haven’t figured out a way, do you have any taps?, cant you do the old epoxy thing, tap threads, and then cast the gasket, if your worried about the strength then make the threads deeper,
Or you could use nuts and bolts for the threaded section, and bore holes in the nuts

I'm still working on a lot of ideas at the moment so it might happen

the one problem with th cartridge design is that the projectile could snag on the link between the cart and the barrel, the is obviously bad bcause unless you have a lot of luck and it gives the projectile backspin. any ideas on how to avoid this?

I never saw that as a problem to be honest, I figured the projectile would be sucked into the barrel just as it would be in a cloud or vortex BBMG.

Looks like this prototype is one step closer to getting built, here's what I received this morning

Ah nice!
Brand new machined parts
So beautiful!

cool!
I found this patent of tippmann. Its a cartridge idea> piston like:
http://www.freepatentsonline.com/20070017406.pdf

Interesting, pretty much the same idea I was working on here.

However, note that this is intended for a revolver mechanism from what the patent indicates, in my case I want it to generate enough force to operate a blowback mechanism.

jackssmirkingrevenge wrote: However, note that this is intended for a revolver mechanism from what the patent indicates, in my case I want it to generate enough force to operate a blowback mechanism.

Ah k, I couldnt find your other post so I posted it here. Yeah I dont think a blowback cartridge would be possilbe due to limited air in it. Once the pressure and the volume go up, the weight also increases. So there is a tradeoff> in other words its ganna be difficult to get it right.

Btw how far are you now on this project now? I c some machined parts. You only have to make the main tank''(small) now?