I disagree
The vented shroud is quite effective and a decent distance from the fore end grip.
The chances of burning through a couple of mags that quickly, under stressful conditions are minimal at best.
Maybe someone at the range doing mag dumps could make it happen, but if there was an RCO there, during a training run, or even a practice session, they would give the shooter hell and likely report it. The little 7.62x25 round, in the ppsh41, is quite hot and quite effective when used by skilled shooters.
There are stories about them being used in very stressful combat conditions, where the chambers got so hot, they cooked off the rounds, until the magazine was empty. I can't see it happening. The ppsh41 is a blowback smg, that fires from an open bolt. Much more robust, reliable, IMHO, than the ubiquitous STEN, which had slightly different trigger/sear arrangement and there wasn't a lot wrong with the STEN, again IMHO.
I liked to rest the bottom of the drum mag on my forearm or in my palm, when using one. Very little climb with short 3-5 round bursts but it had a tendency to move the shots to the right, if memory serves. It was a long time ago.