Dual-friction barrels

Post questions and info about combustion (flammable vapor) powered launchers here. This includes discussion about fuels, ratios, ignition systems and anything else relevant to launchers powered by igniting things like hairspray or propane.

Postby fullmetaljacket » Wed Feb 21, 2007 12:21 am

I've used this idea on my small pneumatics.

<img src="http://i164.photobucket.com/albums/u28/hw97karbine/misc/hvbb.jpg" title="" >

The rubber sleeve at the end of the barrel is of a smaller inner diameter than the projectile, meaning that it effectively holds it in place until there is sufficient pressure to start moving.
Posts: 1684
Joined: Mon Jun 14, 2004 1:33 pm

Postby spuzi14 » Wed Feb 21, 2007 3:40 pm

So now what does this mean for energy? The projectile is allowed to gather more total energy due to the high starting amount (since it's being held longer)? Or will this allow a two foot barrel to perform like a three foot barrel?
Posts: 1235
Joined: Tue Aug 09, 2005 1:02 pm
Location: USA

Postby SPG » Wed Feb 21, 2007 3:51 pm

I think above all this has to be something simple, very simple. Why? because if it gets any more complicated than a union and a burst disc, you way as well just have a union and a burst disc. I'm sure we can think of complicated ways to make this work, but what we need to do is think of simpler ways.
Posts: 983
Joined: Mon Jan 12, 2004 4:51 am
Location: France

Return to Combustion Launchers