If you load lots of an object (Rods for example) and activate the Accelerator the objects go flying, and insta-kill whatever they hit. Me and some guy tested this twice. Both times it worked, so its reproducible. Same happens from rapid firing Vending machines, though they do less damage, but they still do quite a bit much for a vending machine.
Found another bug. Items launched from vending machines are heat seeking missiles. As long as they have line of sight, they hit you. Even threw obstacles
Is it a set number of times? I rode the gravitrons a lot in a recent round, stopped for about 20 minutes and then went onto it again and immediately gibbed before completing finishing one loop.
I dont think its a set amount.. i once built a station wide space transport and it gibbed one guy the second he hit a direction change,it was horribly funny to watch.