Printed this great model today with the single shot trigger. I'm suffering the same issue as others have (firing multiple bands in one go), I'm going to check if I can remedy this by upscaling the cog. Also I did file down the pins and noticed that my cog and trigger where a little lose on the pin. I made some little spacers to remedy this and center the cog and trigger.
I'll let you guys know how the upscale went.