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Posted: Tue Apr 05, 2011 9:03 am
by Labtecpower
I just want to fill the hybrid completely, so if it has 7 bar in the chamber, the pilot would have the same pressure.
I will just machine a piston with a rubber ring BTB came up with.
In this way I could also just use it as a pneumatic.
Posted: Sat Apr 09, 2011 12:42 am
by irisher
I am considering having another go at this hybrid cartridge business but I am unsure of how my current design will fare so I hope to get some second opinions.

My question to you guys is this; assuming the ignition is at the front of the cartridge, do you think that the preigntion force on the other side will fight the combustion wave and rob power or will it be overcome immediately once the piston cracks open?
Posted: Mon Apr 11, 2011 12:02 am
by jackssmirkingrevenge
The pressure created in the combustion chamber will be far greater than the pre-ignition pressure in the "pilot" area so I don't think you should worry about that.
Also, if this is for a cartridge and you intend to build a number of them, why not have a floating o-ring instead of a one way valve, or just ditch the o-rings altogether and just have a tight fitting piston?
Posted: Mon Apr 11, 2011 12:07 am
by JDP12
OMG.. JSR's alive!!!
Are you back already?
Posted: Mon Apr 11, 2011 12:08 am
by jackssmirkingrevenge
Nope, still in sunny EspaƱa... but my laptop's buggered so I only have internet access at work :s
Posted: Mon Apr 11, 2011 12:41 am
by JDP12
ah.. I see you quickly made up for your absence with a multitude of posts

Posted: Mon Apr 11, 2011 1:19 pm
by Lockednloaded
Have y'all seen davidvanini's pneumatic burst disk cartridges? Would the same concept not work in copper as a hybrid?
Posted: Mon Apr 11, 2011 1:26 pm
by JDP12
yess.... sort of..
you're suggesting forcing the burst disc into two pipes? I posted a topic about this some time ago, but the problem is that it is extremely hard to do this and get a seal. Especially the type of seal that would be required for high mixes. A union is really your best bet for working with the high pressures generated by a hybrid.
Posted: Tue Apr 12, 2011 10:08 am
by jackssmirkingrevenge
I concur with the above, you need a threaded or cam type connector to hold the burst disk even for fairly low mixes.
Posted: Sat Apr 16, 2011 5:40 am
by jackssmirkingrevenge
back in my home testing range after a couple of weeks away, decided to have some fun with my hybrid at 15x using a large steel spike as a projectile
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The first shot is with a rather fragile alloy sabot that deformed on ignition, you can see particles emerge from the muzzle before the projectile and the shot is fairly weak.
The second shot on the other hand was with a steel sabot (basically a cut down CO<sub>2</sub> capsule, it was stopped by the granite slab backing the wood...
Posted: Sat Apr 16, 2011 6:38 am
by Crna Legija
My hybrid is
winning aswell, but i only have a 1ml syringe and need to inject 7.2ml for 10x so iv only done a few 5x shots so far. When my bro goes back to work he can get me a few 10ml syringes. Its was surprisingly loud.
Posted: Sun Apr 17, 2011 8:40 pm
by Skywalker
@ Crna Legija: dang it, I was in the office too! Blaspheming Sheen-roller....
Posted: Sat Apr 23, 2011 3:26 pm
by JDP12
JSR-- any updates on this?
Maybe actually make it into a gun instead of a testbed hmm??
Posted: Sat Apr 23, 2011 3:46 pm
by jackssmirkingrevenge
I'm going to be away for a few more weeks after Monday, but when I return there's a good chance you'll see a "finished" launcher develop

Posted: Sat Apr 23, 2011 3:59 pm
by JDP12
what would that be.. your sedond? After the Beas 10mm pneumatic?
Hahaha.