SpudFiles

This is the design for the next cannon I plan to build. IBS stands for inverted barrel system. I know people have use this design before, so it works. It will be a 3" chamber and a 2" barrel. The ratio is .88:1. It will use metered propane and use a bbq igniter for ignition. The fan will be mounted in the handle. If any suggestions, fire away.

I think that you might want 2+ ignition points to make up for the obstruction caused by the barrel.
Other than that, great! I hope that works well.
It would be cool if you had a RPG type sight on top, not that that's really important.

I was wondering about adding in an extra set of electrodes. It couldnt hurt. And I do plan to add some type of sights since I am basing it off the actual Javelin.

You could have two pop up crosshair sights, one at the front, one at the back, that would be sooo cool!! Make it so that you just push a release button and they pop up.

That reminds me of another design that is based of an anti tank launcher where you pull the barrel slides out of the chamber and locks and seals before it comes all the way out. I know it's possible and I'll keep working on it.