pneumatic mortar?

[Alster370]

My "magic dust" worked brilliantly when tested yesterday, I would like to build a simple mortar to launch this high into the air.

I don't want to rely on something like a lifting powder so I thought a pneumatic would be best?

I would need to fire "object" about an inch in diameter and I can use ggdt to work out pressures and altitudes, im simply putting this thread up to ask if you think this is a suitable method for what I want to accomplish?

Thanks

[Goats spudz]

I thought "explosives" werent allowed to be discussed? anyhow you could use a piston like in a coaxial with a spring behind it and release air from the chamber by dropping the projectile on it.

[Alster370]

Well they cant be discussed, mostly so that people don't replicate the recipe and injure themselves and the fact that this isn't that type of forum, so that's why i haven't mentioned what it is or anything about it but its obvious what it is to most people on this forum.

My only concern with your design is that the near instant flow rate of the qev could prevent the mortar from working properly, which is why I would have a non coax design, with a ball valve after the qev to lower the flowrate. Having a qev in the system makes the launches more consistent than say, a piece of string attached to a ball valve.

[Fnord]

I think you guys should edit down your posts a little to keep the intended use a little more vague. Is there a reason you don't want to use a combustion? It would simplify ignition, and variable power could be achieved by either altering the projectile position, or adding a ball valve to the chamber to allow some of the pressure to bleed off when firing.

[Alster370]

edit down your posts a little to keep the intended use a little more vague.

Good point, posts edited

Is there a reason you don't want to use a combustion?

its not quite as precise as using air, plus I already have most of the fittings for a pneumatic on hand so the cost would be reduced. But mostly for concern that the heat and speed of the combustion could make for a premature firing, but i suppose it would light the fuse when triggered.

[Fnord]

I kinda figured you'd want the thing ignited when the gun was triggered, by means of an appropriately made fuse. Please look up shell design on the appropriate forum before attempting this, I've only done a bare minimum of this type of stuff, but I can tell you that timing isn't always as straightforward as it might seem.