Yes it's very possible to use more compression fittings to make this design but as with just the solder fittings I used they would need a lot of modification.
Every tee I used has had the middle constricted section dremeled and sanded out so the piping could slide clean through and with no breaks in the chamber to the tee branch.
Also the end of the chamber isn't reaally what it seems, if you have a look at this concept picture I knocked up when designing it you'll see exactly what the chamber end is and thats not possible with just compression fittings. Probably be possible to secure the end with a glued in block but the way I did it means it's as safe as any other connection on the cannon.
To be honest this was my first time fixing up pipe and it's very worthwhile to solder or glue things instead of using compression fittings when you can. It looks smarter, weighs less and costs less
