Thanks ThunderCactus. Yep this set up operates everything on the pull of a trigger; gearbox, box mag motor, and tracer activate simultaneously. I like the feed tube idea, maybe cutting/splicing with a length of 1/4" pvc tube to allow the LEDs unobstructed access to the bbs might also work well.
As noted in my earlier post, I reinforced the whole set up with hot glue. I also wired up a toggle switch so that the tracer can be turned on/off on a whim to prevent giving away the users position with tracers.
As for how it performed, I unfortunately only got to use it once due to the late hour the sun went down and we had total darkness (11:00 or later), early hour it came back up (3:00 am, I kid you not), and an ~2 hour maneuver by three squads for a three sided attack on our objective, a small village. When we did assault, I lit up the town like the "fourth of ****** July" providing an extremely effective distraction for my squad and the two other squads moving in. I was about 175 feet away and you could clearly see the tracers ricocheting off structures and Opfor.
I used a mix of 50/50 0.28 tracer bio and non tracer bio that worked very effectively. The four LEDs might be overkill as I think it saturates the LED as much as they can be, but I would rather have too much light and saturate it fully. For anyone considering this, I wouldn't use less than 3 LEDs.