I was messing around with my 1936 S/42 shooter a couple years back trying to improve the the trigger, and took too much metal off the sear bar and it went full auto.....it was insanely fast. I'm pretty experienced with automatic fireams and it ripped off a mag much faster than a MAC 11 .380....I'd say it was running at about 2000 rpm. I can see why there was never a successful P08 conversion fielded by the military. I'm guessing the rate is because of the low mass and short travel of the breechblock.
In case the NSA is listening, I threw the sear bar away