Ok so we now have several options: normal pressure butane or propane : not so much power so it's a no from me normal pressure air without explosion : needs more pressure for the same power, not viable Hectmarr's pressurized air/butane or propane, compressed when inserting the projectile in the shell...

Here's how I would make a hybrid cartridge using the epoxy casting construction method , assuming you do not have access to anything more complex than a drill and hacksaw: https://i.imgur.com/0Onrrjq.png It's doable, but naturally more complex to build and also to fill as well. You have to inject t...

Hello! Welcome ! Thank you :D Interesting what you are trying to do. It is something different from the common and threshing combustion launchers that are seen everywhere. Thanks, I really like the idea of shells but I only saw a few projects using it. Do you plan to include the stoichiometric mixt...

Welcome to the forum! Thanks :D The issue with an atmospheric pressure combustion is that peak pressure is relatively low, so even if you increase the chamber volume, power is not going to be that impressive. It really depends on what you want to achieve. Honestly I don't really know what i want to...

Hi all :) I plan on making propane combustion 40mm grenades. As a first step I want to make the a simple M79 style launcher, breach action and all, to focus on the shell itself. I'll later come to blowback if possible but I want to start easier. I've read a lot of topics on this forum, and came acro...