I SO wish I had video of mine going full auto on me, I'm going to have to try and get some the next time I fool around with it. I run my 6.5 with a carbon fiber pump handle and the return spring on the lower guide rod. The inside of the handle is just a big hole, so the spring can't go anywhere else. And for some reason, that sucker will take off on full auto, completely unassisted for a few shots. I think i've sent about 11 or 12 before the shake & bake stopped feeding and the gun quit. But i must say, when it goes, it goes FAST. I have to assume that with the extremely light pump handle, there's not enough mass to prevent the gun from recocking itself off the blowback, and if I hold the trigger, the AT kicks in thus repeating the process over and over, until the hopper can no longer keep up.
It's really quite amusing, and I did have one person on the field question whether or not my pump had burst fire. I think if I still had my rotor, I would be able to get it going at any time, since it definitely relies on a ball being in the chamber to get the blowback. It doesn't happen every time, but more often that not, should I decide to use the gun, at some point or another it WILL happen.