I've done a little experimenting with resin printers, and they have proven strong enough to handle 150PSI firing. So here is a version of my latest low profile cannon design with the compression nut built in, rather than printed separately. As always, resolution is a huge factor in printing success. Unlike with FDM printers, you'll have to make sure un-cured resin in the ammo ramp can properly drain out. Otherwise, a droplet or two may stick in there and prevent rounds from feeding.
For a fun science experiment, try printing the cannon in transparent resin so you can see what's going on inside.
As before, I have included both print-ready .stl files and the original Fusion 360 files so you can do your own modifications.